:root {
    --primary-color: #4F46E5;
    --secondary-color: #7C3AED;
    --accent-primary: #A78BFA;
    --accent-color: #06b6d4;
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --danger-color: #ef4444;

    --bg-primary: #0D0C1D;
    --bg-secondary: #1A1A2E;
    --bg-tertiary: #211f3d;
    --surface-glass: rgba(255, 255, 255, 0.05);
    --surface-glass-hover: rgba(255, 255, 255, 0.08);
    --surface-glass-strong: rgba(255, 255, 255, 0.12);
    --border-glass: rgba(255, 255, 255, 0.1);
    --border-glass-hover: rgba(255, 255, 255, 0.2);
    --dropdown-bg: #0D0C1D;
    --card-bg: rgba(255, 255, 255, 0.03);
    --card-bg-hover: rgba(255, 255, 255, 0.06);

    --text-primary: #FFFFFF;
    --text-secondary: #9CA3AF;
    --text-tertiary: #6B7280;
    --text-muted: var(--text-secondary);

    --primary: var(--primary-color);
    --primary-hover: #4338CA;
    --secondary: var(--secondary-color);
    --accent: var(--accent-primary);
    --accent-soft: #DDD6FE;
    --success: var(--success-color);
    --warning: var(--warning-color);
    --danger: var(--danger-color);
    --border: var(--border-glass);
    --border-strong: var(--border-glass-hover);

    --shadow-sm: 0 10px 30px rgba(0, 0, 0, 0.2);
    --shadow-md: 0 18px 44px rgba(0, 0, 0, 0.28);
    --shadow-lg: 0 32px 90px rgba(0, 0, 0, 0.35);
    --shadow-glow: 0 0 40px rgba(79, 70, 229, 0.2);

    --radius-sm: 0.55rem;
    --radius-md: 0.9rem;
    --radius-lg: 1.2rem;
    --radius-xl: 1.6rem;
    --radius-2xl: 1.85rem;
    --radius-full: 999px;
    --transition-speed: 0.3s;

    --font: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
}

*,
*::before,
*::after {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    min-height: 100vh;
    font-family: var(--font);
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    position: relative;
    isolation: isolate;
}

body::before {
    content: '';
    position: fixed;
    top: -20%;
    left: -20%;
    width: 60%;
    height: 60%;
    background: radial-gradient(circle, var(--primary-color) 0%, transparent 70%);
    opacity: 0.15;
    filter: blur(100px);
    z-index: -1;
    pointer-events: none;
    animation: pulse-glow-1 15s infinite alternate;
}

body::after {
    content: '';
    position: fixed;
    bottom: -20%;
    right: -20%;
    width: 60%;
    height: 60%;
    background: radial-gradient(circle, var(--accent-primary) 0%, transparent 70%);
    opacity: 0.15;
    filter: blur(100px);
    z-index: -1;
    pointer-events: none;
    animation: pulse-glow-2 12s infinite alternate;
}

@keyframes pulse-glow-1 {
    from { transform: scale(0.8) rotate(0deg); opacity: 0.1; }
    to { transform: scale(1.2) rotate(45deg); opacity: 0.2; }
}

@keyframes pulse-glow-2 {
    from { transform: scale(1.2) rotate(0deg); opacity: 0.2; }
    to { transform: scale(0.8) rotate(-45deg); opacity: 0.1; }
}

a {
    color: var(--text-primary);
    text-decoration: none;
    transition: color var(--transition-speed);
}

a:hover {
    color: var(--accent-primary);
}

button,
input,
select,
textarea {
    font: inherit;
}

img {
    max-width: 100%;
    display: block;
}

ul {
    margin: 0;
    padding: 0;
    list-style: none;
}

::selection {
    background: rgba(79, 70, 229, 0.35);
    color: var(--text-primary);
}

.nav-container {
    position: sticky;
    top: 0;
    z-index: 50;
    background: var(--surface-glass);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-glass);
}

.nav-content {
    max-width: 1280px;
    height: 4rem;
    margin: 0 auto;
    padding: 0 1rem;
    display: flex;
    align-items: center;
}

.nav-links,
.auth-buttons {
    display: none;
}

.auth-buttons-mobile {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(80px, 1fr));
    gap: 0.75rem;
}

.nav-logo-link {
    display: inline-flex;
    align-items: center;
    height: 100%;
    padding: 0.25rem 0;
    margin-right: 1rem;
}

.nav-logo-img {
    height: 32px;
    width: auto;
    max-height: calc(100% - 0.5rem);
    display: block;
}

.nav-link {
    padding: 0.5rem 0.75rem;
    border-radius: 0.375rem;
    color: var(--text-primary);
    display: inline-flex;
    align-items: center;
    white-space: nowrap;
    transition: background-color var(--transition-speed), color var(--transition-speed);
}

.nav-link:hover {
    background-color: var(--surface-glass-hover);
    color: var(--text-primary);
}

.nav-link.active {
    background-color: var(--surface-glass-hover);
    border: 1px solid var(--border-glass);
}

.nav-item.nav-dropdown {
    position: relative;
    display: inline-block;
}

.dropdown-arrow {
    margin-left: 0.35rem;
    font-size: 0.7rem;
    transition: transform 0.15s ease;
}

.nav-dropdown-menu {
    position: absolute;
    top: 100%;
    left: 0;
    min-width: 220px;
    padding: 0.5rem 0;
    background: var(--dropdown-bg);
    backdrop-filter: blur(15px);
    border: 1px solid var(--border-glass);
    border-radius: 0.5rem;
    box-shadow: 0 8px 16px rgba(0, 0, 0, 0.2);
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
    transform: translateY(5px);
    transition: opacity var(--transition-speed) ease, visibility var(--transition-speed) ease, transform var(--transition-speed) ease;
}

.nav-item.nav-dropdown:hover > .nav-dropdown-menu {
    opacity: 1;
    visibility: visible;
    pointer-events: auto;
    transform: translateY(0);
}

.nav-item.nav-dropdown:hover > .nav-dropdown-toggle .dropdown-arrow {
    transform: rotate(180deg);
}

.nav-dropdown-item {
    display: block;
    padding: 0.6rem 1.2rem;
    color: var(--text-primary);
}

.nav-dropdown-item:hover,
.nav-dropdown-item.active {
    background-color: var(--surface-glass-hover);
    color: var(--text-primary);
}

.mobile-menu-button {
    display: block;
    background: none;
    border: 0;
    color: var(--text-primary);
    padding: 0.5rem;
    cursor: pointer;
    transition: opacity var(--transition-speed);
    z-index: 51;
}

.mobile-menu-button:hover {
    opacity: 0.8;
}

.mobile-menu {
    display: none;
    position: fixed;
    left: 0;
    right: 0;
    background: var(--bg-primary);
    backdrop-filter: blur(12px);
    padding: 1rem 0;
    z-index: 49;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
    overflow-y: auto;
    transform: translateY(-100%);
    transition: transform var(--transition-speed) ease-out;
}

.mobile-menu.active {
    display: block;
    transform: translateY(0);
}

.mobile-menu .nav-link:not(.sub-link),
.mobile-menu .mobile-submenu-toggle {
    display: block;
    padding: 0.9rem 1.5rem;
    text-align: left;
    border-bottom: 1px solid var(--border-glass);
    width: 100%;
    color: var(--text-primary);
}

.mobile-menu > *:not(.mobile-menu-section):not(.auth-buttons-mobile):last-of-type {
    border-bottom: none;
}

.mobile-menu .mobile-menu-section:last-of-type > .mobile-submenu-toggle {
    border-bottom: none;
}

.mobile-submenu-toggle {
    background: none;
    border: none;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.mobile-submenu-toggle[aria-expanded="true"] .dropdown-arrow {
    transform: rotate(180deg);
}

.mobile-submenu {
    background-color: rgba(0, 0, 0, 0.1);
    overflow: hidden;
    max-height: 0;
    transition: max-height 0.3s ease-out;
}

.mobile-submenu .sub-link {
    display: block;
    padding: 0.75rem 1.5rem 0.75rem 2.5rem;
    font-size: 0.92rem;
    color: var(--text-secondary);
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

.mobile-menu .auth-buttons-mobile {
    border-top: 1px solid var(--border-glass);
    padding: 1.5rem 1.5rem 1rem;
    margin-top: 1rem;
}

.banner-container {
    width: 100%;
    background: var(--bg-primary);
    position: relative;
    overflow: hidden;
}

.banner-content {
    margin: 0 auto;
    position: relative;
    z-index: 10;
}

.banner-link {
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 0.75rem;
    text-decoration: none;
    color: var(--text-primary);
    background: var(--surface-glass);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-glass);
    text-align: center;
    font-size: 0.875rem;
    transition: opacity 0.3s ease;
}

.banner-link:hover {
    opacity: 0.9;
    color: var(--text-primary);
}

.button {
    padding: 0.75rem 1.5rem;
    border-radius: 0.5rem;
    border: none;
    cursor: pointer;
    transition: all var(--transition-speed);
    font-weight: 500;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    text-align: center;
    font-size: 0.95rem;
}

.button-primary {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: var(--text-primary);
    border: 1px solid transparent;
}

.button-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(79, 70, 229, 0.4);
    color: var(--text-primary);
}

.button-outline,
.button-secondary {
    background: transparent;
    border: 1px solid var(--border-glass);
    color: var(--text-primary);
}

.button-outline:hover,
.button-secondary:hover {
    background: var(--surface-glass-hover);
    border-color: var(--border-glass-hover);
    color: var(--text-primary);
}

.profile-icon,
.submit-icon {
    padding: 10px !important;
}

.profile-menu.show {
    background: var(--bg-primary) !important;
}

.section-shell,
.study-shell {
    width: min(1320px, calc(100% - 2rem));
    margin: 0 auto;
}

.flashcard-app .study-shell {
    width: min(1480px, calc(100% - 2rem));
}

.workspace-header {
    position: relative;
    padding: 1.35rem 0 1rem;
    overflow: hidden;
}

.workspace-header-shell {
    position: relative;
    z-index: 1;
    display: grid;
    grid-template-columns: minmax(0, 1.25fr) minmax(300px, 0.8fr);
    gap: 1.3rem;
    align-items: start;
}

.workspace-heading,
.workspace-meta {
    display: grid;
    gap: 0.85rem;
    align-content: start;
}

.workspace-copy {
    display: grid;
    gap: 0.75rem;
    max-width: 56rem;
}

.workspace-copy h1,
.workspace-copy .hero-subtitle {
    margin: 0;
}

.workspace-copy h1 {
    font-size: clamp(2.3rem, 4vw, 3.7rem);
    line-height: 1.03;
    letter-spacing: -0.04em;
}

.workspace-plan-row {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
}

.workspace-heading .breadcrumb-link,
.workspace-heading .hero-badge {
    margin-bottom: 0;
}

.app-hero {
    position: relative;
    padding: 3.75rem 0 2.25rem;
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    inset: 0;
    pointer-events: none;
}

.hero-grid {
    position: absolute;
    inset: 0;
    background-image:
        linear-gradient(rgba(255, 255, 255, 0.04) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255, 255, 255, 0.04) 1px, transparent 1px);
    background-size: 44px 44px;
    mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.95), transparent);
}

.hero-glow {
    position: absolute;
    border-radius: 999px;
    filter: blur(90px);
}

.hero-glow-a {
    width: 26rem;
    height: 26rem;
    top: -4rem;
    left: -4rem;
    background: rgba(79, 70, 229, 0.28);
}

.hero-glow-b {
    width: 22rem;
    height: 22rem;
    right: 4rem;
    top: 1rem;
    background: rgba(167, 139, 250, 0.24);
}

.app-hero-shell {
    position: relative;
    z-index: 1;
    display: grid;
    grid-template-columns: minmax(0, 1.35fr) minmax(290px, 0.75fr);
    gap: 1.3rem;
    align-items: start;
}

.breadcrumb-link,
.hero-badge,
.usage-pill,
.meta-pill,
.plan-chip,
.info-chip,
.summary-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    width: fit-content;
    padding: 0.55rem 0.95rem;
    border-radius: var(--radius-full);
    background: var(--surface-glass);
    border: 1px solid var(--border);
    backdrop-filter: blur(10px);
}

.breadcrumb-link {
    margin-bottom: 1rem;
    color: var(--text-secondary);
    transition: color 0.15s ease, background-color 0.15s ease;
}

.breadcrumb-link:hover {
    color: var(--text-primary);
    background: var(--surface-glass-hover);
}

.hero-badge {
    margin-bottom: 1rem;
    color: var(--accent-soft);
    font-weight: 700;
}

.hero-copy h1 {
    margin: 0 0 1rem;
    font-size: clamp(2.7rem, 5.8vw, 4.5rem);
    line-height: 1.03;
    letter-spacing: -0.04em;
}

.hero-subtitle,
.panel-copy,
.field-help,
.plan-note-item span,
.flashcard-hint,
.flashcard-source,
.shortcut-strip,
.subpanel-header p,
.recent-deck-time,
.session-status,
.stat-label,
.summary-stat span {
    color: var(--text-secondary);
}

.hero-subtitle {
    max-width: 54rem;
    font-size: 1.06rem;
}

.hero-actions,
.hero-auth-actions,
.lock-actions,
.summary-actions {
    display: flex;
    gap: 0.75rem;
    flex-wrap: wrap;
}

.hero-actions {
    margin: 1.4rem 0 1.1rem;
}

.hero-trust-strip {
    display: flex;
    flex-wrap: wrap;
    gap: 0.85rem;
    color: var(--text-tertiary);
}

.hero-trust-strip span {
    display: inline-flex;
    align-items: center;
    gap: 0.45rem;
}

.hero-panel {
    display: grid;
    gap: 0.9rem;
}

.hero-mini-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 0.75rem;
}

.metric-card,
.glass-panel,
.glass-subpanel,
.stat-card,
.session-summary,
.recent-deck-card {
    background: linear-gradient(180deg, rgba(255, 255, 255, 0.08), rgba(255, 255, 255, 0.03));
    border: 1px solid var(--border);
    box-shadow: var(--shadow-sm);
    backdrop-filter: blur(16px);
}

.metric-card {
    padding: 1rem;
    border-radius: var(--radius-lg);
}

.metric-card strong {
    display: block;
    font-size: 1.45rem;
}

.metric-card span {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.hero-auth-card {
    padding: 1rem 1.1rem;
    border-radius: var(--radius-lg);
    background: rgba(255, 255, 255, 0.04);
    border: 1px solid var(--border);
}

.hero-auth-card p {
    margin: 0 0 1rem;
    color: var(--text-secondary);
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.55rem;
    padding: 0.95rem 1.2rem;
    border-radius: 0.95rem;
    border: 1px solid transparent;
    font-weight: 700;
    line-height: 1.4;
    cursor: pointer;
    font: inherit;
    color: inherit;
    -webkit-appearance: none;
    appearance: none;
    transition: transform 0.15s ease, box-shadow 0.15s ease, background-color 0.15s ease, border-color 0.15s ease;
}

.btn:hover:not(:disabled) {
    transform: translateY(-1px);
}

.btn:disabled {
    opacity: 0.45;
    cursor: not-allowed;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    color: #fff;
    box-shadow: var(--shadow-glow);
}

.btn-primary:hover:not(:disabled) {
    box-shadow: 0 16px 38px rgba(79, 70, 229, 0.3);
}

.btn-secondary {
    background: var(--surface-glass);
    color: var(--text-primary);
    border-color: var(--border);
}

.btn-secondary:hover:not(:disabled) {
    background: var(--surface-glass-hover);
    border-color: var(--border-strong);
}

.btn-large {
    width: 100%;
}

.btn-small,
.btn-compact {
    padding: 0.7rem 0.95rem;
    font-size: 0.9rem;
}

.study-shell {
    padding: 0 0 3rem;
}

.app-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 1.25rem;
    align-items: start;
    max-width: 960px;
    margin: 0 auto;
}

.glass-panel {
    position: relative;
    border-radius: var(--radius-2xl);
    padding: 1.3rem;
    overflow: hidden;
}

.session-panel {
    overflow: visible;
}

.glass-panel::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(180deg, rgba(255, 255, 255, 0.05), transparent 36%);
    pointer-events: none;
}

.session-panel,
.builder-form,
.library-panel {
    position: relative;
    z-index: 1;
}

/* ── Drawer overlay ── */
.drawer-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.55);
    backdrop-filter: blur(4px);
    z-index: 1100;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.3s ease, visibility 0.3s ease;
}

.drawer-overlay.is-open {
    opacity: 1;
    visibility: visible;
}

/* ── Builder drawer ── */
.builder-drawer {
    position: fixed;
    top: 0;
    right: 0;
    width: min(480px, 92vw);
    height: 100vh;
    z-index: 1101;
    background: var(--bg-primary);
    border-left: 1px solid var(--border);
    box-shadow: -8px 0 40px rgba(0, 0, 0, 0.4);
    display: flex;
    flex-direction: column;
    transform: translateX(100%);
    transition: transform 0.35s cubic-bezier(0.22, 1, 0.36, 1);
}

.builder-drawer.is-open {
    transform: translateX(0);
}

.drawer-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1.1rem 1.3rem;
    border-bottom: 1px solid var(--border);
    flex-shrink: 0;
}

.drawer-header h2 {
    margin: 0;
    font-size: 1.15rem;
    line-height: 1.2;
}

.drawer-close {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 2.2rem;
    height: 2.2rem;
    border: 1px solid var(--border);
    border-radius: 0.6rem;
    background: rgba(255, 255, 255, 0.04);
    color: var(--text-secondary);
    font-size: 1.1rem;
    cursor: pointer;
    transition: background 0.15s ease, color 0.15s ease;
}

.drawer-close:hover {
    background: var(--surface-glass-hover);
    color: var(--text-primary);
}

.drawer-body {
    flex: 1;
    overflow-y: auto;
    padding: 1.3rem;
    overscroll-behavior: contain;
}

/* ── Session toolbar ── */
.session-toolbar {
    display: flex;
    gap: 0.65rem;
    margin-bottom: 1.1rem;
    flex-wrap: wrap;
}

.panel-header,
.subpanel-header,
.step-header,
.recent-deck-head,
.progress-copy,
.summary-header {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: 0.9rem;
}

.panel-header {
    margin-bottom: 1.1rem;
}

.panel-kicker {
    display: inline-block;
    margin-bottom: 0.35rem;
    color: var(--accent-soft);
    font-size: 0.8rem;
    font-weight: 700;
    letter-spacing: 0.08em;
    text-transform: uppercase;
}

.panel-header h2,
.step-header h3,
.confidence-copy h3,
.subpanel-header h3,
.summary-header h3 {
    margin: 0;
    line-height: 1.15;
}

.panel-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 0.55rem;
    justify-content: flex-end;
}

.plan-chip,
.usage-pill,
.summary-badge {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.plan-chip {
    align-self: start;
}

.library-panel {
    border-radius: var(--radius-xl);
    padding: 1rem;
    margin-bottom: 1rem;
}

.library-empty {
    padding: 1rem;
    border-radius: 1rem;
    border: 1px dashed var(--border);
    background: rgba(255, 255, 255, 0.02);
    color: var(--text-secondary);
    font-size: 0.94rem;
}

.recent-decks {
    display: grid;
    gap: 0.55rem;
    max-height: 16rem;
    overflow-y: auto;
    padding-right: 0.2rem;
    overscroll-behavior: contain;
}

.recent-deck-card {
    padding: 0.95rem;
    border-radius: 1rem;
}

.recent-deck-card.is-current {
    border-color: rgba(124, 58, 237, 0.38);
    box-shadow: 0 0 0 1px rgba(124, 58, 237, 0.14), var(--shadow-sm);
}

.recent-deck-head strong {
    display: block;
    line-height: 1.25;
}

.recent-deck-head small {
    display: block;
    color: var(--text-secondary);
    margin-top: 0.18rem;
}

.recent-status {
    display: inline-flex;
    align-items: center;
    padding: 0.35rem 0.6rem;
    border-radius: var(--radius-full);
    background: rgba(167, 139, 250, 0.12);
    border: 1px solid rgba(167, 139, 250, 0.18);
    color: var(--accent-soft);
    font-size: 0.78rem;
    font-weight: 700;
    white-space: nowrap;
}

.recent-deck-stats {
    display: flex;
    flex-wrap: wrap;
    gap: 0.65rem;
    color: var(--text-secondary);
    font-size: 0.88rem;
    margin: 0.75rem 0 0.45rem;
}

.recent-deck-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 0.55rem;
    margin-top: 0.75rem;
}

.builder-form {
    display: grid;
    gap: 1rem;
}

.builder-step {
    padding: 1rem;
    border-radius: var(--radius-xl);
    border: 1px solid var(--border);
    background: rgba(255, 255, 255, 0.03);
    display: grid;
    gap: 0.9rem;
}

.step-index {
    flex: 0 0 auto;
    width: 2rem;
    height: 2rem;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: 999px;
    background: rgba(124, 58, 237, 0.14);
    color: var(--accent-soft);
    font-weight: 800;
}

.step-header p {
    margin: 0.25rem 0 0;
    color: var(--text-secondary);
}

.field-group {
    display: grid;
    gap: 0.55rem;
}

.field-grid {
    display: grid;
    gap: 0.9rem;
}

.field-grid-2 {
    grid-template-columns: repeat(2, minmax(0, 1fr));
}

.field-group-wide {
    grid-column: span 2;
}

.field-label {
    font-weight: 700;
    font-size: 0.94rem;
}

.field-input,
.field-select,
.field-textarea {
    width: 100%;
    background: rgba(255, 255, 255, 0.04);
    border: 1px solid var(--border);
    color: var(--text-primary);
    border-radius: 0.95rem;
    padding: 0.9rem 1rem;
    transition: border-color 0.15s ease, background-color 0.15s ease, box-shadow 0.15s ease;
}

.field-select option {
    color: #111827;
}

.field-textarea {
    resize: vertical;
    min-height: 7rem;
}

.format-grid,
.choice-grid,
.selected-files,
.tag-list,
.summary-stats,
.builder-actions,
.plan-note,
.stats-grid,
.session-bottom-grid,
.trophy-grid,
.confidence-grid {
    display: grid;
    gap: 0.75rem;
}

.choice-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
}

.source-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
}

.choice-card {
    cursor: pointer;
}

.choice-card input {
    position: absolute;
    opacity: 0;
    pointer-events: none;
}

.choice-body {
    display: flex;
    align-items: flex-start;
    gap: 0.85rem;
    padding: 1rem 1.1rem;
    border-radius: 1rem;
    border: 1px solid var(--border);
    background: rgba(255, 255, 255, 0.03);
    transition: transform 0.15s ease, border-color 0.15s ease, background-color 0.15s ease, box-shadow 0.15s ease;
}

.choice-body strong {
    display: block;
}

.choice-body small {
    color: var(--text-secondary);
}

.choice-card input:checked + .choice-body {
    border-color: rgba(79, 70, 229, 0.72);
    background: linear-gradient(135deg, rgba(79, 70, 229, 0.18), rgba(124, 58, 237, 0.1));
    box-shadow: 0 10px 24px rgba(79, 70, 229, 0.12);
    transform: translateY(-1px);
}

.choice-card.is-disabled,
.choice-card input:disabled + .choice-body {
    opacity: 0.5;
    cursor: not-allowed;
}

.upload-shell {
    display: grid;
    gap: 0.7rem;
    padding: 1rem;
    border-radius: 1rem;
    border: 1px solid var(--border);
    background: rgba(255, 255, 255, 0.03);
}

.upload-meta {
    display: grid;
    gap: 0.3rem;
    color: var(--text-secondary);
    font-size: 0.92rem;
}

.upload-meta span {
    display: inline-flex;
    align-items: center;
    gap: 0.45rem;
}

.selected-files {
    grid-template-columns: repeat(auto-fit, minmax(140px, max-content));
}

.file-chip {
    display: inline-flex;
    align-items: center;
    gap: 0.45rem;
    padding: 0.45rem 0.75rem;
    border-radius: var(--radius-full);
    background: rgba(167, 139, 250, 0.12);
    color: #ede9fe;
    font-size: 0.88rem;
}

.research-source-section.is-hidden {
    display: none;
}

.research-source-header {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: 1rem;
    margin-bottom: 0.85rem;
}

.research-source-header .field-help {
    margin: 0.35rem 0 0;
}

.research-source-limit {
    display: inline-flex;
    align-items: center;
    padding: 0.45rem 0.75rem;
    border-radius: var(--radius-full);
    border: 1px solid var(--border);
    background: rgba(255, 255, 255, 0.04);
    color: var(--text-secondary);
    font-size: 0.88rem;
    white-space: nowrap;
}

.research-source-list {
    display: grid;
    gap: 0.75rem;
}

.research-source-card {
    display: grid;
    gap: 0.6rem;
    padding: 0.95rem;
    border-radius: 1rem;
    border: 1px solid var(--border);
    background: rgba(255, 255, 255, 0.03);
}

.research-source-controls {
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto;
    gap: 0.75rem;
    align-items: center;
}

.research-fetch-btn {
    min-width: 7.5rem;
}

.research-source-status {
    font-size: 0.92rem;
    color: var(--text-secondary);
}

.research-source-status.is-success {
    color: #bfdbfe;
}

.research-source-status.is-error {
    color: #fecaca;
}

.research-source-status.is-loading {
    color: #ddd6fe;
}

.research-source-status.is-stale {
    color: #fde68a;
}

.advanced-options {
    border: 1px solid var(--border);
    border-radius: 1rem;
    background: rgba(255, 255, 255, 0.025);
}

.advanced-options summary {
    list-style: none;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 0.75rem;
    padding: 0.95rem 1rem;
    cursor: pointer;
    font-weight: 700;
}

.advanced-options summary::-webkit-details-marker {
    display: none;
}

.advanced-options summary small {
    color: var(--text-secondary);
    font-weight: 500;
}

.advanced-options[open] summary {
    border-bottom: 1px solid var(--border);
}

.advanced-options-body {
    padding: 1rem;
    display: grid;
    gap: 1rem;
}

.builder-alert {
    padding: 0.95rem 1rem;
    border-radius: 1rem;
    border: 1px solid rgba(239, 68, 68, 0.25);
    background: rgba(239, 68, 68, 0.12);
    color: #fecaca;
}

.builder-alert.is-hidden,
.session-summary.is-hidden {
    display: none;
}

.plan-note {
    grid-template-columns: repeat(3, minmax(0, 1fr));
}

.plan-note-item {
    padding: 0.9rem;
    border-radius: 1rem;
    border: 1px solid var(--border);
    background: rgba(255, 255, 255, 0.025);
}

.plan-note-item strong {
    display: block;
    margin-bottom: 0.2rem;
}

.panel-lock {
    position: absolute;
    inset: 1rem;
    z-index: 4;
    display: grid;
    place-items: center;
    gap: 0.8rem;
    text-align: center;
    background: rgba(13, 12, 29, 0.76);
    backdrop-filter: blur(18px);
    border: 1px solid var(--border);
    border-radius: var(--radius-xl);
}

.lock-badge {
    width: 3rem;
    height: 3rem;
    display: grid;
    place-items: center;
    border-radius: 1rem;
    background: linear-gradient(135deg, rgba(79, 70, 229, 0.22), rgba(124, 58, 237, 0.18));
    color: var(--accent-soft);
}

.overview-grid {
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto;
    gap: 0.85rem;
    margin-bottom: 1rem;
    align-items: start;
}

.overview-card {
    padding: 1rem 1.1rem;
    border-radius: 1rem;
    background: rgba(255, 255, 255, 0.035);
    border: 1px solid var(--border);
}

.overview-card p {
    margin: 0.6rem 0 0;
    color: var(--text-secondary);
}

.overview-aside {
    display: grid;
    gap: 0.6rem;
}

.meta-pill.emphasis {
    background: linear-gradient(135deg, rgba(79, 70, 229, 0.16), rgba(124, 58, 237, 0.1));
}

.stats-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    margin-bottom: 1.25rem;
}

.stat-card {
    padding: 1rem;
    border-radius: 1rem;
}

.stat-card strong {
    font-size: 1.45rem;
}

.coach-banner {
    padding: 1rem 1.1rem;
    border-radius: 1rem;
    margin-bottom: 1.25rem;
    background: linear-gradient(135deg, rgba(79, 70, 229, 0.18), rgba(124, 58, 237, 0.1));
    border: 1px solid rgba(124, 58, 237, 0.25);
    color: #e0e7ff;
}

.progress-shell {
    margin-bottom: 1rem;
}

.progress-copy {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-bottom: 0.45rem;
}

.progress-bar {
    width: 100%;
    height: 0.65rem;
    border-radius: var(--radius-full);
    background: rgba(255, 255, 255, 0.06);
    overflow: hidden;
}

.progress-bar span {
    display: block;
    width: 10%;
    height: 100%;
    border-radius: inherit;
    background: linear-gradient(90deg, var(--accent), var(--primary));
    transition: width 0.3s ease;
}

.session-summary {
    padding: 1rem 1.1rem;
    border-radius: 1.1rem;
    margin-bottom: 1rem;
}

.summary-stats {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    margin: 0.9rem 0;
}

.summary-stat {
    padding: 0.85rem;
    border-radius: 0.95rem;
    background: rgba(255, 255, 255, 0.045);
    border: 1px solid var(--border);
}

.summary-stat strong {
    display: block;
    margin-top: 0.15rem;
    font-size: 1.15rem;
}

.flashcard-stage {
    position: relative;
    display: grid;
    gap: 1rem;
    margin: 1.6rem 0 1.75rem;
    padding: clamp(1rem, 2.5vw, 1.45rem);
    border-radius: calc(var(--radius-2xl) + 0.15rem);
    border: 1px solid rgba(255, 255, 255, 0.08);
    background:
        linear-gradient(180deg, rgba(255, 255, 255, 0.07), rgba(255, 255, 255, 0.02)),
        radial-gradient(circle at top left, rgba(6, 182, 212, 0.14), transparent 32%),
        radial-gradient(circle at bottom right, rgba(124, 58, 237, 0.18), transparent 40%),
        rgba(13, 12, 29, 0.72);
    box-shadow: var(--shadow-lg);
    overflow: hidden;
    isolation: isolate;
}

.flashcard-stage::before,
.flashcard-stage::after {
    content: '';
    position: absolute;
    inset: 0;
    pointer-events: none;
}

.flashcard-stage::before {
    background: linear-gradient(120deg, rgba(255, 255, 255, 0.08), transparent 38%, transparent 62%, rgba(255, 255, 255, 0.03));
}

.flashcard-stage::after {
    inset: 1px;
    border-radius: inherit;
    border: 1px solid rgba(255, 255, 255, 0.04);
}

.flashcard {
    position: relative;
    display: block;
    width: 100%;
    min-height: clamp(22rem, 54vw, 28rem);
    padding: 0;
    border: 0;
    background: transparent;
    text-align: left;
    cursor: pointer;
    -webkit-perspective: 1200px;
    perspective: 1200px;
    -webkit-appearance: none;
    appearance: none;
    font: inherit;
    color: inherit;
    outline: none;
}

.flashcard-inner {
    position: relative;
    width: 100%;
    min-height: clamp(22rem, 54vw, 28rem);
    -webkit-transform-style: preserve-3d;
    transform-style: preserve-3d;
    transition: transform 0.7s cubic-bezier(0.22, 1, 0.36, 1);
    will-change: transform;
}

.flashcard.flipped .flashcard-inner {
    -webkit-transform: rotateY(180deg);
    transform: rotateY(180deg);
}

.flashcard-face {
    position: absolute;
    top: 0;
    right: 0;
    bottom: 0;
    left: 0;
    -webkit-backface-visibility: hidden;
    backface-visibility: hidden;
    overflow: hidden;
    border-radius: calc(var(--radius-2xl) - 0.15rem);
    padding: clamp(1.25rem, 3vw, 1.7rem);
    border: 1px solid rgba(255, 255, 255, 0.1);
    background:
        linear-gradient(160deg, rgba(255, 255, 255, 0.14), rgba(255, 255, 255, 0.05) 32%, rgba(9, 8, 26, 0.92) 100%);
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    gap: 1.2rem;
    box-shadow: 0 24px 60px rgba(4, 7, 20, 0.38);
    color: white;
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.flashcard-face::before,
.flashcard-face::after {
    content: '';
    position: absolute;
    pointer-events: none;
}

.flashcard-face::before {
    top: -20%;
    right: -8%;
    width: 14rem;
    height: 14rem;
    border-radius: 50%;
    background: radial-gradient(circle, rgba(255, 255, 255, 0.18), transparent 68%);
    opacity: 0.85;
}

.flashcard-face::after {
    inset: 0;
    background: linear-gradient(140deg, rgba(255, 255, 255, 0.05), transparent 45%, rgba(255, 255, 255, 0.02));
}

.flashcard-front {
    background:
        linear-gradient(155deg, rgba(6, 182, 212, 0.2), rgba(79, 70, 229, 0.16) 42%, rgba(13, 12, 29, 0.94) 100%),
        linear-gradient(160deg, rgba(255, 255, 255, 0.12), rgba(255, 255, 255, 0.03));
}

.flashcard-back {
    -webkit-transform: rotateY(180deg);
    transform: rotateY(180deg);
    background:
        linear-gradient(155deg, rgba(16, 185, 129, 0.18), rgba(124, 58, 237, 0.16) 42%, rgba(13, 12, 29, 0.94) 100%),
        linear-gradient(160deg, rgba(255, 255, 255, 0.12), rgba(255, 255, 255, 0.03));
}

.flashcard:hover .flashcard-front,
.flashcard:focus-visible .flashcard-front,
.flashcard.flipped:hover .flashcard-back,
.flashcard.flipped:focus-visible .flashcard-back {
    border-color: rgba(167, 139, 250, 0.42);
    box-shadow: 0 28px 72px rgba(3, 7, 18, 0.48), 0 0 0 1px rgba(167, 139, 250, 0.12);
}

.face-label {
    display: inline-flex;
    width: fit-content;
    position: relative;
    z-index: 1;
    padding: 0.45rem 0.8rem;
    border-radius: var(--radius-full);
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.08);
    color: rgba(255, 255, 255, 0.92);
    backdrop-filter: blur(12px);
    font-size: 0.78rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.12em;
}

.flashcard-front h3,
.flashcard-back p {
    margin: 0;
    position: relative;
    z-index: 1;
}

.flashcard-front h3 {
    max-width: 18ch;
    font-size: clamp(1.75rem, 3vw, 2.45rem);
    line-height: 1.08;
    letter-spacing: -0.04em;
}

.flashcard-back p {
    max-width: 38ch;
    font-size: clamp(1.08rem, 2vw, 1.28rem);
    line-height: 1.6;
    color: rgba(255, 255, 255, 0.9);
}

.flashcard-support {
    display: grid;
    gap: 0.85rem;
    padding-top: 1rem;
    border-top: 1px solid rgba(255, 255, 255, 0.08);
}

.card-meta-row,
.card-source-row {
    display: flex;
    flex-wrap: wrap;
    gap: 0.85rem;
    align-items: center;
    justify-content: space-between;
}

.stage-actions {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 0.75rem;
}

.stage-actions .btn {
    width: 100%;
    justify-content: center;
    padding-block: 0.9rem;
    border-radius: 1rem;
    background: linear-gradient(180deg, rgba(255, 255, 255, 0.08), rgba(255, 255, 255, 0.03));
    backdrop-filter: blur(12px);
}

.stage-actions .btn:hover:not(:disabled) {
    background: linear-gradient(180deg, rgba(255, 255, 255, 0.12), rgba(255, 255, 255, 0.05));
}

.stage-actions .btn i {
    color: var(--accent-soft);
}

.info-chip {
    color: var(--text-secondary);
    font-size: 0.88rem;
}

.tag-list {
    grid-template-columns: repeat(auto-fit, minmax(90px, max-content));
}

.tag-chip {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.35rem 0.7rem;
    border-radius: var(--radius-full);
    background: rgba(167, 139, 250, 0.12);
    border: 1px solid rgba(167, 139, 250, 0.16);
    color: var(--accent-soft);
    font-size: 0.82rem;
    white-space: nowrap;
}

.source-link,
.source-item-link {
    color: var(--accent-soft);
    text-decoration: underline;
    text-decoration-color: rgba(167, 139, 250, 0.35);
    text-underline-offset: 0.15rem;
}

.shortcut-strip {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 0.8rem 1rem;
    border-radius: var(--radius-full);
    border: 1px dashed rgba(255, 255, 255, 0.16);
    background: rgba(255, 255, 255, 0.03);
    font-size: 0.88rem;
    letter-spacing: 0.01em;
    text-align: center;
}

.flashcard-hint {
    margin: 0;
    padding: 0.9rem 1rem;
    border-radius: 1rem;
    border: 1px solid rgba(6, 182, 212, 0.18);
    background: linear-gradient(135deg, rgba(6, 182, 212, 0.1), rgba(79, 70, 229, 0.08));
}

.confidence-shell {
    display: grid;
    gap: 0.8rem;
    padding: 1rem;
    border-radius: 1.35rem;
    background: rgba(255, 255, 255, 0.04);
    border: 1px solid rgba(255, 255, 255, 0.08);
    box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.04);
}

.confidence-prompt {
    margin: 0;
    padding-top: 0.9rem;
    border-top: 1px solid rgba(255, 255, 255, 0.08);
    color: var(--text-secondary);
    font-size: 0.92rem;
    text-align: center;
    justify-self: center;
    max-width: 58ch;
}

.confidence-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 0.75rem;
}

.confidence-btn {
    --level-color: rgba(167, 139, 250, 0.9);
    -webkit-appearance: none;
    appearance: none;
    font: inherit;
    position: relative;
    display: grid;
    gap: 0.35rem;
    justify-items: start;
    min-height: 4.75rem;
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: 1rem;
    padding: 0.85rem;
    background: linear-gradient(180deg, rgba(255, 255, 255, 0.08), rgba(255, 255, 255, 0.03));
    color: var(--text-primary);
    font-weight: 700;
    font-size: 0.92rem;
    line-height: 1.2;
    text-align: left;
    cursor: pointer;
    overflow: hidden;
    box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.04);
    transition: transform 0.15s ease, border-color 0.15s ease, background-color 0.15s ease, box-shadow 0.15s ease;
}

.confidence-btn::after {
    content: '';
    position: absolute;
    left: 0.85rem;
    right: 0.85rem;
    bottom: 0.65rem;
    height: 0.18rem;
    border-radius: var(--radius-full);
    background: var(--level-color);
    opacity: 0.55;
}

.confidence-btn.level-1 {
    --level-color: rgba(248, 113, 113, 0.95);
}

.confidence-btn.level-2 {
    --level-color: rgba(251, 191, 36, 0.95);
}

.confidence-btn.level-3 {
    --level-color: rgba(196, 181, 253, 0.95);
}

.confidence-btn.level-4 {
    --level-color: rgba(52, 211, 153, 0.95);
}

.confidence-btn span {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 1.9rem;
    padding: 0.2rem 0.5rem;
    margin-top: 0.05rem;
    border-radius: var(--radius-full);
    border: 1px solid rgba(255, 255, 255, 0.08);
    background: rgba(255, 255, 255, 0.08);
    color: var(--text-primary);
    font-size: 0.74rem;
    font-weight: 700;
}

.confidence-btn:hover:not(:disabled) {
    transform: translateY(-2px);
    border-color: rgba(255, 255, 255, 0.16);
    box-shadow: 0 16px 34px rgba(2, 6, 23, 0.28);
}

.confidence-btn.level-1:hover:not(:disabled) {
    border-color: rgba(248, 113, 113, 0.42);
    background: linear-gradient(180deg, rgba(248, 113, 113, 0.16), rgba(255, 255, 255, 0.04));
}

.confidence-btn.level-2:hover:not(:disabled) {
    border-color: rgba(251, 191, 36, 0.42);
    background: linear-gradient(180deg, rgba(251, 191, 36, 0.16), rgba(255, 255, 255, 0.04));
}

.confidence-btn.level-3:hover:not(:disabled) {
    border-color: rgba(196, 181, 253, 0.42);
    background: linear-gradient(180deg, rgba(167, 139, 250, 0.18), rgba(255, 255, 255, 0.04));
}

.confidence-btn.level-4:hover:not(:disabled) {
    border-color: rgba(52, 211, 153, 0.42);
    background: linear-gradient(180deg, rgba(52, 211, 153, 0.16), rgba(255, 255, 255, 0.04));
}

.session-bottom-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 1rem;
}

.glass-subpanel {
    border-radius: 1.15rem;
    padding: 1.15rem;
}

.subpanel-header {
    margin-bottom: 0.75rem;
}

.info-list {
    display: grid;
    gap: 0.55rem;
}

.info-list li {
    position: relative;
    padding-left: 1rem;
    color: var(--text-secondary);
}

.info-list li::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0.56rem;
    width: 0.38rem;
    height: 0.38rem;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--accent), var(--primary));
}

.info-list li.is-empty {
    padding-left: 0;
    color: var(--text-tertiary);
}

.info-list li.is-empty::before {
    display: none;
}

.info-list.compact {
    margin-top: 0.85rem;
}

.trophy-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
}

.trophy-card {
    display: grid;
    gap: 0.3rem;
    padding: 0.9rem;
    border-radius: 1rem;
    border: 1px solid var(--border);
    background: rgba(255, 255, 255, 0.03);
}

.trophy-card.unlocked {
    border-color: rgba(250, 204, 21, 0.38);
    background: linear-gradient(135deg, rgba(250, 204, 21, 0.12), rgba(79, 70, 229, 0.12));
}

.trophy-card i {
    color: #facc15;
}

.trophy-card small {
    color: var(--text-secondary);
}

.field-input:focus,
.field-select:focus,
.field-textarea:focus,
.btn:focus-visible,
.flashcard:focus-visible,
.confidence-btn:focus-visible,
.edit-card-btn:focus-visible,
.flag-card-btn:focus-visible,
.shuffle-btn:focus-visible,
.nav-link:focus-visible,
.nav-dropdown-item:focus-visible,
.mobile-menu-button:focus-visible,
.mobile-submenu-toggle:focus-visible,
.source-link:focus-visible,
.source-item-link:focus-visible {
    outline: none;
    border-color: rgba(167, 139, 250, 0.55);
    box-shadow: 0 0 0 4px rgba(167, 139, 250, 0.14);
}

.choice-card input:focus-visible + .choice-body {
    outline: 3px solid rgba(167, 139, 250, 0.22);
    outline-offset: 3px;
}

/* ── Card transition ── */
.flashcard-stage.is-transitioning .flashcard-inner {
    opacity: 0;
    transform: translateX(30px);
    transition: opacity 0.18s ease, transform 0.18s ease;
}

.flashcard-stage.is-transitioning.is-entering .flashcard-inner {
    opacity: 1;
    transform: translateX(0);
}

/* ── Card counter ── */
.card-counter {
    display: flex;
    align-items: center;
    justify-content: center;
    justify-self: start;
    gap: 0.4rem;
    padding: 0.65rem 1rem;
    border-radius: var(--radius-full);
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.08), rgba(255, 255, 255, 0.03));
    border: 1px solid rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    color: var(--text-secondary);
    font-size: 0.88rem;
    font-weight: 600;
    margin-bottom: 0;
}

.card-counter strong {
    color: var(--text-primary);
}

/* ── Keyboard shortcut modal ── */
.shortcut-modal-overlay {
    position: fixed;
    inset: 0;
    z-index: 200;
    display: grid;
    place-items: center;
    background: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(6px);
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.2s ease, visibility 0.2s ease;
}

.shortcut-modal-overlay.is-visible {
    opacity: 1;
    visibility: visible;
}

.shortcut-modal {
    width: min(460px, calc(100% - 2rem));
    padding: 1.5rem;
    border-radius: var(--radius-2xl);
    background: linear-gradient(180deg, rgba(26, 26, 46, 0.98), rgba(13, 12, 29, 0.98));
    border: 1px solid var(--border-glass-hover);
    box-shadow: var(--shadow-lg);
}

.shortcut-modal h3 {
    margin: 0 0 1rem;
    font-size: 1.15rem;
}

.shortcut-modal-close {
    float: right;
    background: none;
    border: none;
    color: var(--text-secondary);
    cursor: pointer;
    font-size: 1.1rem;
    padding: 0.25rem;
}

.shortcut-modal-close:hover {
    color: var(--text-primary);
}

.shortcut-list {
    display: grid;
    gap: 0.6rem;
}

.shortcut-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
    padding: 0.55rem 0;
    border-bottom: 1px solid var(--border);
}

.shortcut-row:last-child {
    border-bottom: none;
}

.shortcut-key {
    display: inline-flex;
    align-items: center;
    gap: 0.35rem;
}

.shortcut-key kbd {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 2rem;
    padding: 0.3rem 0.55rem;
    border-radius: 0.5rem;
    background: rgba(255, 255, 255, 0.08);
    border: 1px solid var(--border-glass-hover);
    color: var(--text-primary);
    font-family: var(--font);
    font-size: 0.82rem;
    font-weight: 700;
}

/* ── Inline card editing ── */
.flashcard-face [contenteditable="true"] {
    outline: none;
    border-radius: 0.5rem;
    padding: 0.25rem 0.4rem;
    margin: -0.25rem -0.4rem;
    background: rgba(79, 70, 229, 0.12);
    border: 1px dashed rgba(167, 139, 250, 0.4);
    cursor: text;
}

.card-edit-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 0.65rem;
    margin-top: 0.15rem;
}

.edit-card-btn,
.flag-card-btn,
.shuffle-btn {
    -webkit-appearance: none;
    appearance: none;
    font: inherit;
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    flex: 1 1 10rem;
    justify-content: center;
    padding: 0.65rem 0.9rem;
    border-radius: 0.95rem;
    border: 1px solid rgba(255, 255, 255, 0.08);
    background: rgba(255, 255, 255, 0.05);
    backdrop-filter: blur(10px);
    color: var(--text-secondary);
    font-size: 0.84rem;
    font-weight: 600;
    cursor: pointer;
    transition: background-color 0.15s ease, border-color 0.15s ease, color 0.15s ease, transform 0.15s ease;
}

.edit-card-btn:hover,
.flag-card-btn:hover,
.shuffle-btn:hover {
    background: var(--surface-glass-hover);
    border-color: var(--border-strong);
    color: var(--text-primary);
    transform: translateY(-1px);
}

.flag-card-btn.is-flagged {
    border-color: rgba(245, 158, 11, 0.5);
    background: rgba(245, 158, 11, 0.12);
    color: #fde68a;
}

/* ── Session history chart ── */
.session-history-panel {
    margin-top: 0.75rem;
}

.history-chart {
    display: flex;
    align-items: flex-end;
    gap: 3px;
    height: 48px;
    padding: 0.5rem 0;
}

.history-bar {
    flex: 1;
    min-width: 6px;
    max-width: 24px;
    border-radius: 3px 3px 0 0;
    background: linear-gradient(180deg, var(--accent), var(--primary));
    transition: height 0.3s ease;
    position: relative;
}

.history-bar:hover {
    opacity: 0.8;
}

.history-bar[data-tooltip]:hover::after {
    content: attr(data-tooltip);
    position: absolute;
    bottom: calc(100% + 6px);
    left: 50%;
    transform: translateX(-50%);
    padding: 0.3rem 0.55rem;
    border-radius: 0.4rem;
    background: rgba(13, 12, 29, 0.95);
    border: 1px solid var(--border);
    color: var(--text-primary);
    font-size: 0.75rem;
    white-space: nowrap;
    pointer-events: none;
    z-index: 10;
}

.history-empty {
    padding: 0.75rem;
    color: var(--text-tertiary);
    font-size: 0.88rem;
}

/* ── Compact saved decks ── */
.recent-deck-card {
    padding: 0.7rem 0.85rem;
}

.recent-deck-head strong {
    font-size: 0.9rem;
}

.recent-deck-head small {
    font-size: 0.78rem;
}

.recent-deck-stats {
    font-size: 0.8rem;
    margin: 0.45rem 0 0.3rem;
    gap: 0.5rem;
}

.recent-deck-actions {
    gap: 0.4rem;
    margin-top: 0.5rem;
}

.recent-deck-actions .btn {
    padding: 0.45rem 0.7rem;
    font-size: 0.78rem;
}

.library-panel {
    padding: 0.85rem;
}

.library-panel .subpanel-header {
    margin-bottom: 0.5rem;
}

.library-panel .subpanel-header h3 {
    font-size: 0.95rem;
}

.library-panel .subpanel-header p {
    font-size: 0.82rem;
}

/* ── Styled file input ── */
.file-input {
    position: relative;
    padding: 0;
    border: 0;
    background: none;
    cursor: pointer;
}

.file-input::file-selector-button {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    padding: 0.6rem 1.1rem;
    border: 1px solid var(--border);
    border-radius: var(--radius-full);
    background: linear-gradient(135deg, rgba(79, 70, 229, 0.15), rgba(124, 58, 237, 0.1));
    color: var(--accent-soft);
    font-family: var(--font);
    font-size: 0.88rem;
    font-weight: 600;
    cursor: pointer;
    margin-right: 0.75rem;
    transition: background 0.2s ease, border-color 0.2s ease;
}

.file-input::file-selector-button:hover {
    background: linear-gradient(135deg, rgba(79, 70, 229, 0.25), rgba(124, 58, 237, 0.18));
    border-color: var(--border-strong);
}

.file-input::-webkit-file-upload-button {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    padding: 0.6rem 1.1rem;
    border: 1px solid var(--border);
    border-radius: var(--radius-full);
    background: linear-gradient(135deg, rgba(79, 70, 229, 0.15), rgba(124, 58, 237, 0.1));
    color: var(--accent-soft);
    font-family: var(--font);
    font-size: 0.88rem;
    font-weight: 600;
    cursor: pointer;
    margin-right: 0.75rem;
    transition: background 0.2s ease, border-color 0.2s ease;
}

.file-input::-webkit-file-upload-button:hover {
    background: linear-gradient(135deg, rgba(79, 70, 229, 0.25), rgba(124, 58, 237, 0.18));
    border-color: var(--border-strong);
}

/* ── Print styles ── */
@media print {
    body::before,
    body::after,
    .hero-bg,
    .workspace-header,
    .builder-drawer,
    .drawer-overlay,
    .session-toolbar,
    .nav-container,
    .mobile-menu,
    .cookie-consent-banner,
    .stage-actions,
    .confidence-shell,
    .shortcut-strip,
    .builder-actions,
    .session-summary,
    .shortcut-modal-overlay,
    .card-edit-actions,
    .flashcard-support .edit-card-btn,
    .flashcard-support .flag-card-btn {
        display: none !important;
    }

    body {
        background: #fff;
        color: #111;
    }

    .app-grid {
        grid-template-columns: 1fr;
    }

    .glass-panel,
    .glass-subpanel,
    .stat-card,
    .flashcard-face,
    .coach-banner,
    .overview-card,
    .trophy-card,
    .confidence-btn {
        background: #fff !important;
        border-color: #ddd !important;
        box-shadow: none !important;
        backdrop-filter: none !important;
        color: #111 !important;
        -webkit-print-color-adjust: exact;
        print-color-adjust: exact;
    }

    .flashcard {
        perspective: none;
        min-height: auto;
    }

    .flashcard-inner {
        transform: none !important;
        min-height: auto;
    }

    .flashcard-face {
        position: relative;
        backface-visibility: visible;
        page-break-inside: avoid;
        margin-bottom: 1rem;
    }

    .flashcard-back {
        transform: none;
    }

    .face-label,
    .panel-kicker,
    .info-chip,
    .tag-chip,
    .meta-pill {
        color: #555 !important;
        background: #f3f4f6 !important;
        border-color: #ddd !important;
    }

    .text-secondary,
    .text-muted,
    .info-list li,
    .stat-label,
    .coach-banner,
    .overview-card p {
        color: #444 !important;
    }

    .progress-bar {
        background: #e5e7eb !important;
    }

    .progress-bar span {
        background: #6366f1 !important;
    }
}

@media (max-width: 1200px) {
    .app-hero-shell,
    .workspace-header-shell {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 900px) {
    .choice-grid,
    .source-grid,
    .field-grid-2,
    .plan-note,
    .stats-grid,
    .summary-stats,
    .session-bottom-grid,
    .trophy-grid,
    .hero-mini-grid {
        grid-template-columns: 1fr;
    }

    .field-group-wide {
        grid-column: auto;
    }

    .panel-header,
    .subpanel-header,
    .step-header,
    .progress-copy,
    .summary-header {
        flex-direction: column;
        align-items: flex-start;
    }

    .panel-actions {
        justify-content: flex-start;
    }

    .overview-grid {
        grid-template-columns: 1fr;
    }

    .research-source-header,
    .research-source-controls {
        grid-template-columns: 1fr;
        display: grid;
    }

    .card-counter {
        justify-content: flex-start;
    }

    .card-meta-row,
    .card-source-row {
        align-items: flex-start;
    }
}

@media (max-width: 859px) {
    .nav-links,
    .auth-buttons {
        display: none;
    }

    .mobile-menu-button {
        display: block;
        margin-left: auto;
    }

    .mobile-menu {
        top: 3.5rem;
        max-height: calc(100vh - 3.5rem);
    }

    .nav-logo-img {
        height: 64px;
    }
}

@media (min-width: 860px) {
    .nav-links,
    .auth-buttons {
        display: flex;
    }

    .mobile-menu-button {
        display: none;
    }

    .mobile-menu {
        display: none !important;
    }

    .nav-links {
        gap: 0.5rem;
        align-items: center;
        margin-left: 1rem;
        margin-right: auto;
    }

    .auth-buttons {
        gap: 0.5rem;
        align-items: center;
        margin-left: 1rem;
    }

    .nav-logo-img {
        height: 64px;
    }
}

@media (max-width: 640px) {
    .section-shell,
    .study-shell {
        width: min(100%, calc(100% - 1rem));
    }

    .workspace-header {
        padding-top: 1rem;
    }

    .app-hero {
        padding-top: 3rem;
    }

    .glass-panel,
    .glass-subpanel,
    .builder-step,
    .session-summary {
        padding: 1rem;
    }

    .flashcard-stage {
        padding: 0.9rem;
    }

    .flashcard,
    .flashcard-inner {
        min-height: 16rem;
    }

    .confidence-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

    .confidence-btn {
        min-height: 4.2rem;
        padding: 0.75rem;
        font-size: 0.8rem;
    }

    .confidence-btn span {
        font-size: 0.7rem;
    }

    .hero-actions,
    .hero-auth-actions,
    .lock-actions,
    .stage-actions,
    .summary-actions,
    .recent-deck-actions {
        flex-direction: column;
        width: 100%;
    }

    .hero-actions .btn,
    .hero-auth-actions .btn,
    .lock-actions .btn,
    .stage-actions .btn,
    .summary-actions .btn,
    .recent-deck-actions .btn {
        width: 100%;
    }

    .stage-actions {
        grid-template-columns: 1fr;
    }

    .card-counter {
        justify-self: stretch;
        justify-content: center;
    }

    .card-edit-actions {
        flex-direction: column;
    }

    .tag-list {
        grid-template-columns: 1fr 1fr;
    }

    .shortcut-modal {
        width: calc(100% - 1rem);
    }
}