: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 (shared) ─────────────────────────────────────────── */
.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; }

/* ── Layout ───────────────────────────────────────────────── */
.study-shell {
    width: min(1340px, calc(100% - 2rem));
    margin: 0 auto;
    padding: 0 0.5rem;
}

.app-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 1.25rem;
    align-items: start;
    padding-bottom: 4rem;
    max-width: 960px;
    margin: 0 auto;
}

/* ── Hero / header ────────────────────────────────────────── */
.workspace-header {
    position: relative;
    overflow: hidden;
    padding: 2rem 0 1.5rem;
    border-bottom: 1px solid var(--border);
    margin-bottom: 1.75rem;
}

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

.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: 48px 48px;
    mask-image: radial-gradient(ellipse 65% 50% at 50% 40%, #000 20%, transparent 100%);
}

.hero-glow {
    position: absolute;
    border-radius: 50%;
    filter: blur(90px);
    opacity: 0.2;
    pointer-events: none;
}
.hero-glow-a { width: 420px; height: 420px; top: -120px; left: -60px; background: var(--primary); }
.hero-glow-b { width: 340px; height: 340px; bottom: -100px; right: -40px; background: var(--accent); }

.workspace-header-shell {
    position: relative;
    display: grid;
    gap: 1.3rem;
}

.breadcrumb-link {
    display: inline-flex; align-items: center; gap: 0.4rem;
    font-size: 0.85rem; color: var(--text-secondary);
    margin-bottom: 0.5rem;
}
.breadcrumb-link:hover { color: var(--text-primary); }

.hero-badge {
    display: inline-flex; align-items: center; gap: 0.5rem;
    padding: 0.45rem 0.9rem;
    border-radius: var(--radius-full);
    background: linear-gradient(135deg, rgba(79,70,229,0.25), rgba(124,58,237,0.15));
    border: 1px solid rgba(79,70,229,0.3);
    font-size: 0.8rem; font-weight: 600;
    margin-bottom: 0.65rem;
    width: fit-content;
}
.hero-badge i { color: var(--accent); }

.workspace-copy h1 {
    font-size: clamp(1.6rem, 3.5vw, 2.4rem);
    font-weight: 800;
    line-height: 1.2;
    margin: 0 0 0.6rem;
    background: linear-gradient(135deg, #fff 0%, var(--accent) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 0.95rem;
    color: var(--text-secondary);
    line-height: 1.6;
    margin: 0;
    max-width: 560px;
}

/* workspace meta (right) */
.workspace-meta {
    display: flex; flex-direction: column; gap: 0.75rem;
}

.usage-pill {
    display: inline-flex; align-items: center; gap: 0.5rem;
    padding: 0.55rem 1rem;
    border-radius: var(--radius-full);
    background: var(--surface-glass);
    border: 1px solid var(--border);
    font-size: 0.82rem; font-weight: 600;
    width: fit-content;
}
.usage-pill i { color: var(--warning); }

.workspace-plan-row {
    display: flex; gap: 0.5rem; flex-wrap: wrap;
}

.plan-chip {
    display: inline-flex; align-items: center;
    padding: 0.35rem 0.75rem;
    border-radius: var(--radius-full);
    background: linear-gradient(135deg, rgba(79,70,229,0.2), rgba(124,58,237,0.12));
    border: 1px solid rgba(79,70,229,0.3);
    font-size: 0.75rem; font-weight: 700;
    text-transform: uppercase; letter-spacing: 0.03em;
}

.meta-pill {
    display: inline-flex; align-items: center; gap: 0.4rem;
    padding: 0.35rem 0.7rem;
    border-radius: var(--radius-full);
    background: var(--surface-glass);
    border: 1px solid var(--border);
    font-size: 0.75rem;
}
.meta-pill i { font-size: 0.7rem; color: var(--text-secondary); }

.hero-mini-grid {
    display: grid; grid-template-columns: repeat(3, 1fr); gap: 0.5rem;
}

.metric-card {
    padding: 0.65rem 0.7rem;
    border-radius: var(--radius-md);
    background: var(--surface-glass);
    border: 1px solid var(--border);
    text-align: center;
}
.metric-card strong { display: block; font-size: 1.1rem; font-weight: 800; }
.metric-card span { font-size: 0.7rem; color: var(--text-secondary); }

.hero-auth-card {
    padding: 1rem;
    border-radius: var(--radius-lg);
    background: var(--surface-glass);
    border: 1px solid var(--border);
}
.hero-auth-card p { margin: 0 0 0.75rem; font-size: 0.88rem; color: var(--text-secondary); }
.hero-auth-actions { display: flex; gap: 0.5rem; }

/* ── Glass panels ─────────────────────────────────────────── */
.glass-panel {
    position: relative;
    background: linear-gradient(180deg, rgba(255,255,255,0.08), rgba(255,255,255,0.03));
    border: 1px solid var(--border);
    backdrop-filter: blur(16px);
    border-radius: var(--radius-2xl);
    box-shadow: var(--shadow-sm);
    padding: 1.5rem;
    overflow: hidden;
}
.glass-panel::before {
    content: '';
    position: absolute; inset: 0;
    background: linear-gradient(180deg, rgba(255,255,255,0.05), transparent 36%);
    border-radius: inherit;
    pointer-events: none;
}

.panel-header {
    display: flex; justify-content: space-between; align-items: flex-start;
    margin-bottom: 1.25rem;
    position: relative;
}

.panel-kicker {
    display: block;
    font-size: 0.72rem; font-weight: 700;
    text-transform: uppercase; letter-spacing: 0.06em;
    color: var(--accent);
    margin-bottom: 0.3rem;
}

.panel-header h2 {
    margin: 0 0 0.25rem;
    font-size: 1.35rem; font-weight: 800;
}

.panel-copy {
    margin: 0;
    font-size: 0.85rem;
    color: var(--text-secondary);
    line-height: 1.5;
}

.panel-actions {
    display: flex; gap: 0.4rem; flex-wrap: wrap;
    margin-top: 0.25rem;
}

/* ── Builder panel (left sidebar) ─────────────────────────── */
.builder-panel {
    position: relative;
}

.panel-lock {
    display: flex; flex-direction: column; align-items: center; justify-content: center;
    text-align: center;
    padding: 2rem 1.5rem;
    border-radius: var(--radius-lg);
    background: var(--surface-glass);
    border: 1px dashed var(--border-strong);
    margin-bottom: 1.25rem;
}
.lock-badge {
    width: 3.5rem; height: 3.5rem;
    display: flex; align-items: center; justify-content: center;
    border-radius: 50%;
    background: linear-gradient(135deg, rgba(79,70,229,0.2), rgba(124,58,237,0.12));
    margin-bottom: 0.75rem;
    font-size: 1.2rem; color: var(--accent);
}
.panel-lock h3 { margin: 0 0 0.4rem; font-size: 1.1rem; }
.panel-lock p { margin: 0 0 1rem; font-size: 0.85rem; color: var(--text-secondary); max-width: 320px; }
.lock-actions { display: flex; gap: 0.5rem; }

/* sub-panel (saved guides) */
.glass-subpanel {
    background: linear-gradient(180deg, rgba(255,255,255,0.05), rgba(255,255,255,0.02));
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 1rem 1.1rem;
    margin-bottom: 1.25rem;
    position: relative;
}
.subpanel-header h3 { margin: 0 0 0.15rem; font-size: 0.95rem; font-weight: 700; }
.subpanel-header p { margin: 0; font-size: 0.78rem; color: var(--text-secondary); }

.library-empty {
    padding: 1rem 0;
    font-size: 0.82rem;
    color: var(--text-tertiary);
    text-align: center;
}

.recent-guides { display: flex; flex-direction: column; gap: 0.4rem; margin-top: 0.6rem; }

.saved-guide-card {
    display: flex; align-items: center; justify-content: space-between;
    padding: 0.65rem 0.8rem;
    border-radius: var(--radius-md);
    background: var(--card-bg);
    border: 1px solid var(--border);
    cursor: pointer;
    transition: background var(--transition-speed), border-color var(--transition-speed);
}
.saved-guide-card:hover {
    background: var(--card-bg-hover);
    border-color: var(--border-strong);
}
.saved-guide-card.is-current {
    border-color: rgba(79,70,229,0.45);
    box-shadow: 0 12px 28px rgba(79,70,229,0.12);
}

.saved-guide-info { min-width: 0; flex: 1; }
.saved-guide-info strong { display: block; font-size: 0.85rem; font-weight: 600; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.saved-guide-info small { font-size: 0.72rem; color: var(--text-secondary); }

.saved-guide-actions { display: flex; gap: 0.35rem; flex-shrink: 0; margin-left: 0.5rem; }

.saved-guide-btn {
    background: none; border: none; cursor: pointer;
    color: var(--text-tertiary); font-size: 0.8rem;
    padding: 0.3rem; border-radius: var(--radius-sm);
    transition: color var(--transition-speed), background var(--transition-speed);
}
.saved-guide-btn:hover { color: var(--text-primary); background: var(--surface-glass); }
.saved-guide-btn.is-delete:hover { color: var(--danger); }

.saved-guide-progress {
    width: 3rem; height: 0.3rem;
    border-radius: var(--radius-full);
    background: rgba(255,255,255,0.08);
    overflow: hidden; margin-top: 0.3rem;
}
.saved-guide-progress-fill {
    height: 100%;
    border-radius: inherit;
    background: var(--success);
    transition: width 0.4s ease;
}

/* ── Builder form ─────────────────────────────────────────── */
.builder-form { display: flex; flex-direction: column; gap: 1.25rem; position: relative; }

.builder-step {
    padding: 1rem 1.1rem;
    border-radius: var(--radius-lg);
    background: var(--card-bg);
    border: 1px solid var(--border);
}

.step-header {
    display: flex; gap: 0.75rem; align-items: flex-start;
    margin-bottom: 1rem;
}

.step-index {
    display: flex; align-items: center; justify-content: center;
    width: 2rem; height: 2rem; flex-shrink: 0;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    color: #fff; font-size: 0.8rem; font-weight: 800;
}

.step-header h3 { margin: 0; font-size: 1rem; font-weight: 700; }
.step-header p { margin: 0.15rem 0 0; font-size: 0.8rem; color: var(--text-secondary); }

.field-grid { display: grid; gap: 0.85rem; }
.field-grid-2 { grid-template-columns: 1fr 1fr; }
.field-group { display: flex; flex-direction: column; gap: 0.35rem; }
.field-group-wide { grid-column: 1 / -1; }

.field-label { font-size: 0.82rem; font-weight: 600; color: var(--text-secondary); }

.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: var(--radius-md);
    padding: 0.9rem 1rem;
    transition: border-color 0.15s ease, background-color 0.15s ease;
}
.field-input:focus, .field-select:focus, .field-textarea:focus {
    outline: none;
    border-color: var(--border-strong);
    background-color: rgba(255,255,255,0.06);
    box-shadow: 0 0 0 3px rgba(79,70,229,0.1);
}
.field-textarea { resize: vertical; min-height: 4.5rem; }
.field-select { appearance: none; cursor: pointer; background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath fill='%239CA3AF' d='M6 8.825L.35 3.175l.7-.7L6 7.425l4.95-4.95.7.7z'/%3E%3C/svg%3E"); background-repeat: no-repeat; background-position: right 1rem center; padding-right: 2.5rem; }
.field-help { font-size: 0.76rem; color: var(--text-tertiary); margin-top: 0.2rem; }

.file-input {
    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);
}
.upload-shell { display: flex; flex-direction: column; gap: 0.5rem; }
.upload-meta { display: flex; flex-direction: column; gap: 0.2rem; }
.upload-meta span { font-size: 0.75rem; color: var(--text-tertiary); display: flex; align-items: center; gap: 0.35rem; }
.selected-files { display: flex; flex-direction: column; gap: 0.25rem; }
.file-chip {
    display: inline-flex; align-items: center; gap: 0.45rem;
    width: fit-content;
    padding: 0.45rem 0.7rem;
    border-radius: var(--radius-full);
    background: var(--surface-glass);
    border: 1px solid var(--border);
    font-size: 0.75rem;
    color: var(--text-secondary);
}
.file-chip i { color: var(--accent); }

/* choice cards (radio) */
.choice-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 0.5rem; }
.source-grid { grid-template-columns: 1fr 1fr; }

.choice-card { cursor: pointer; }
.choice-card input { opacity: 0; position: absolute; pointer-events: none; }
.choice-body {
    display: flex; flex-direction: column; gap: 0.15rem;
    padding: 0.85rem 1rem;
    border-radius: var(--radius-md);
    border: 1px solid var(--border);
    background: var(--card-bg);
    transition: all 0.15s ease;
}
.choice-body strong { font-size: 0.88rem; }
.choice-body small { font-size: 0.74rem; 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 { opacity: 0.45; pointer-events: none; }

/* toggle cards (checkbox) */
.toggle-grid { display: flex; flex-direction: column; gap: 0.5rem; }

.toggle-card { cursor: pointer; display: block; }
.toggle-card input { opacity: 0; position: absolute; pointer-events: none; }
.toggle-body {
    display: flex; align-items: center; gap: 0.85rem;
    padding: 0.85rem 1rem;
    border-radius: var(--radius-md);
    border: 1px solid var(--border);
    background: var(--card-bg);
    transition: all 0.15s ease;
}
.toggle-icon {
    display: flex; align-items: center; justify-content: center;
    width: 2.4rem; height: 2.4rem; flex-shrink: 0;
    border-radius: var(--radius-md);
    background: var(--surface-glass);
    color: var(--text-secondary);
    font-size: 0.95rem;
    transition: all 0.15s ease;
}
.toggle-copy { display: flex; flex-direction: column; gap: 0.1rem; }
.toggle-copy strong { font-size: 0.88rem; }
.toggle-copy small { font-size: 0.74rem; color: var(--text-secondary); }

.toggle-card input:checked + .toggle-body {
    border-color: rgba(79,70,229,0.72);
    background: linear-gradient(135deg, rgba(79,70,229,0.12), rgba(124,58,237,0.06));
}
.toggle-card input:checked + .toggle-body .toggle-icon {
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    color: #fff;
}

/* advanced options */
.advanced-options {
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    background: var(--card-bg);
    overflow: hidden;
}
.advanced-options summary {
    display: flex; flex-direction: column; gap: 0.1rem;
    padding: 0.85rem 1rem;
    cursor: pointer; list-style: none;
    font-weight: 600; font-size: 0.9rem;
}
.advanced-options summary::-webkit-details-marker { display: none; }
.advanced-options summary small { font-size: 0.76rem; color: var(--text-secondary); font-weight: 400; }
.advanced-options-body { padding: 0 1rem 1rem; }

/* builder actions / alert */
.builder-alert {
    padding: 0.85rem 1rem;
    border-radius: var(--radius-md);
    font-size: 0.85rem;
    font-weight: 600;
}
.builder-alert.is-hidden { display: none; }
.builder-alert.is-error { background: rgba(239,68,68,0.15); border: 1px solid rgba(239,68,68,0.3); color: #fca5a5; }
.builder-alert.is-success { background: rgba(16,185,129,0.15); border: 1px solid rgba(16,185,129,0.3); color: #6ee7b7; }
.builder-alert.is-info { background: rgba(79,70,229,0.15); border: 1px solid rgba(79,70,229,0.3); color: var(--accent-soft); }

.builder-actions { display: flex; gap: 0.75rem; flex-wrap: wrap; }

.plan-note {
    display: grid; grid-template-columns: repeat(3, 1fr); gap: 0.5rem;
    padding: 0.75rem; border-radius: var(--radius-md);
    background: var(--surface-glass); border: 1px solid var(--border);
}
.plan-note-item { text-align: center; }
.plan-note-item strong { display: block; font-size: 0.72rem; color: var(--text-secondary); font-weight: 700; text-transform: uppercase; letter-spacing: 0.03em; }
.plan-note-item span { font-size: 0.78rem; }

/* ── Buttons ──────────────────────────────────────────────── */
.btn {
    display: inline-flex; align-items: center; justify-content: center; gap: 0.55rem;
    padding: 0.95rem 1.25rem;
    border-radius: var(--radius-md);
    font-weight: 700; font-size: 0.9rem;
    border: 1px solid transparent;
    cursor: pointer;
    transition: transform 0.15s ease, box-shadow 0.15s ease, background 0.15s ease;
    text-decoration: none;
}
.btn:disabled { opacity: 0.4; pointer-events: none; }

.btn-primary {
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    color: #fff; border-color: transparent;
    box-shadow: 0 18px 38px rgba(79,70,229,0.28);
}
.btn-primary:hover { transform: translateY(-1px); box-shadow: 0 22px 42px rgba(79,70,229,0.34); }

.btn-secondary {
    background: rgba(255,255,255,0.06);
    border-color: var(--border);
    color: var(--text-primary);
}
.btn-secondary:hover { background: rgba(255,255,255,0.09); }

.btn-compact { padding: 0.55rem 0.9rem; font-size: 0.82rem; }
.btn-large { padding: 1rem 1.5rem; font-size: 0.95rem; }
.btn-full { width: 100%; }
.btn-small { padding: 0.45rem 0.7rem; font-size: 0.78rem; }

/* ── Guide viewer (right panel) ───────────────────────────── */
.guide-panel { position: relative; }

/* Tabs */
.guide-tabs {
    display: flex; gap: 0.25rem;
    padding: 0.35rem;
    border-radius: var(--radius-lg);
    background: var(--surface-glass);
    border: 1px solid var(--border);
    margin-bottom: 1.25rem;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
}

.guide-tab {
    flex: 1; min-width: 0;
    display: flex; align-items: center; justify-content: center; gap: 0.4rem;
    padding: 0.7rem 0.5rem;
    border-radius: var(--radius-md);
    background: transparent;
    border: none; cursor: pointer;
    color: var(--text-secondary);
    font-size: 0.82rem; font-weight: 600;
    white-space: nowrap;
    transition: all 0.2s ease;
}
.guide-tab:hover { color: var(--text-primary); background: rgba(255,255,255,0.04); }
.guide-tab.active {
    color: #fff;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    box-shadow: 0 4px 12px rgba(79,70,229,0.25);
}
.guide-tab i { font-size: 0.78rem; }

.guide-tab-content { display: none; position: relative; }
.guide-tab-content.active { display: block; }

/* Overview tab */
.guide-overview { display: flex; flex-direction: column; gap: 1rem; }

.coach-card {
    display: flex; gap: 0.85rem; align-items: flex-start;
    padding: 1rem 1.15rem;
    border-radius: var(--radius-lg);
    background: linear-gradient(135deg, rgba(79,70,229,0.12), rgba(124,58,237,0.06));
    border: 1px solid rgba(79,70,229,0.25);
}
.coach-icon {
    display: flex; align-items: center; justify-content: center;
    width: 2.8rem; height: 2.8rem; flex-shrink: 0;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    color: #fff; font-size: 1.1rem;
}
.coach-text strong { display: block; font-size: 0.82rem; color: var(--accent); margin-bottom: 0.2rem; }
.coach-text p { margin: 0; font-size: 0.88rem; color: var(--text-secondary); line-height: 1.55; }

.overview-text p { margin: 0; font-size: 0.92rem; color: var(--text-secondary); line-height: 1.7; }

.overview-stats {
    display: grid; grid-template-columns: repeat(2, 1fr); gap: 0.6rem;
}
.stat-card {
    display: flex; align-items: center; gap: 0.75rem;
    padding: 0.85rem 1rem;
    border-radius: var(--radius-md);
    background: var(--card-bg);
    border: 1px solid var(--border);
}
.stat-card i { font-size: 1.1rem; color: var(--accent); }
.stat-card strong { display: block; font-size: 0.92rem; font-weight: 700; }
.stat-card span { font-size: 0.72rem; color: var(--text-secondary); }

.study-tips-card, .resources-card, .knowledge-gaps-card {
    padding: 1rem 1.15rem;
    border-radius: var(--radius-lg);
    background: var(--card-bg);
    border: 1px solid var(--border);
}
.study-tips-card h4, .resources-card h4, .knowledge-gaps-card h4 {
    margin: 0 0 0.65rem;
    font-size: 0.9rem; font-weight: 700;
    display: flex; align-items: center; gap: 0.5rem;
}
.study-tips-card h4 i { color: var(--accent); }
.resources-card h4 i { color: var(--success); }
.knowledge-gaps-card h4 i { color: var(--warning); }
.knowledge-gaps-card.is-hidden { display: none; }

.study-tips-card li, .resources-card li, .knowledge-gaps-card li {
    padding: 0.4rem 0;
    font-size: 0.85rem;
    color: var(--text-secondary);
    line-height: 1.5;
    border-bottom: 1px solid rgba(255,255,255,0.04);
    position: relative;
    padding-left: 1.1rem;
}
.study-tips-card li::before, .resources-card li::before, .knowledge-gaps-card li::before {
    content: '';
    position: absolute; left: 0; top: 0.75rem;
    width: 0.35rem; height: 0.35rem;
    border-radius: 50%;
    background: var(--accent);
}
.resources-card li::before { background: var(--success); }
.knowledge-gaps-card li::before { background: var(--warning); }
.study-tips-card li:last-child, .resources-card li:last-child, .knowledge-gaps-card li:last-child { border-bottom: none; }

/* Sections tab */
.sections-nav {
    display: flex; gap: 0.35rem; flex-wrap: wrap;
    margin-bottom: 1rem;
}

.section-nav-btn {
    padding: 0.55rem 0.85rem;
    border-radius: var(--radius-full);
    background: var(--surface-glass);
    border: 1px solid var(--border);
    color: var(--text-secondary);
    font-size: 0.78rem; font-weight: 600;
    cursor: pointer;
    transition: all 0.15s ease;
}
.section-nav-btn:hover { background: var(--surface-glass-hover); color: var(--text-primary); }
.section-nav-btn.active {
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    color: #fff; border-color: transparent;
}

.section-card {
    display: none;
    flex-direction: column; gap: 1rem;
}
.section-card.active { display: flex; }

.section-title-bar {
    display: flex; justify-content: space-between; align-items: flex-start;
    gap: 0.75rem;
}
.section-title-bar h3 { margin: 0; font-size: 1.15rem; font-weight: 800; }

.section-difficulty {
    display: inline-flex; align-items: center; gap: 0.3rem;
    padding: 0.3rem 0.65rem;
    border-radius: var(--radius-full);
    font-size: 0.72rem; font-weight: 700;
    background: var(--surface-glass);
    border: 1px solid var(--border);
    flex-shrink: 0;
}

.section-summary {
    font-size: 0.9rem; color: var(--text-secondary); line-height: 1.6;
    padding: 0.75rem 1rem;
    border-radius: var(--radius-md);
    background: linear-gradient(135deg, rgba(79,70,229,0.08), rgba(124,58,237,0.04));
    border: 1px solid rgba(79,70,229,0.15);
    margin: 0;
}

.section-content {
    font-size: 0.9rem; color: var(--text-secondary); line-height: 1.75;
    white-space: pre-wrap;
}

.section-key-terms {
    display: grid; grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); gap: 0.5rem;
}

.key-term-card {
    padding: 0.75rem 0.9rem;
    border-radius: var(--radius-md);
    background: var(--card-bg);
    border: 1px solid var(--border);
}
.key-term-card strong {
    display: block;
    font-size: 0.85rem; font-weight: 700;
    color: var(--accent);
    margin-bottom: 0.2rem;
}
.key-term-card span { font-size: 0.82rem; color: var(--text-secondary); line-height: 1.5; }

.section-tips, .section-mistakes {
    padding: 0.85rem 1rem;
    border-radius: var(--radius-md);
}
.section-tips {
    background: rgba(16,185,129,0.08);
    border: 1px solid rgba(16,185,129,0.2);
}
.section-mistakes {
    background: rgba(239,68,68,0.08);
    border: 1px solid rgba(239,68,68,0.2);
}
.section-tips h4, .section-mistakes h4 {
    margin: 0 0 0.5rem;
    font-size: 0.85rem; font-weight: 700;
    display: flex; align-items: center; gap: 0.4rem;
}
.section-tips h4 { color: var(--success); }
.section-mistakes h4 { color: var(--danger); }
.section-tips li, .section-mistakes li {
    font-size: 0.82rem;
    color: var(--text-secondary);
    padding: 0.25rem 0 0.25rem 1rem;
    position: relative; line-height: 1.5;
}
.section-tips li::before, .section-mistakes li::before {
    content: '';
    position: absolute; left: 0; top: 0.6rem;
    width: 0.3rem; height: 0.3rem;
    border-radius: 50%;
}
.section-tips li::before { background: var(--success); }
.section-mistakes li::before { background: var(--danger); }

/* Takeaways tab */
.takeaways-grid {
    display: grid; gap: 0.6rem;
}

.takeaway-card {
    display: flex; align-items: flex-start; gap: 0.85rem;
    padding: 1rem 1.1rem;
    border-radius: var(--radius-md);
    background: var(--card-bg);
    border: 1px solid var(--border);
    transition: transform 0.15s ease, border-color 0.15s ease;
}
.takeaway-card:hover {
    transform: translateY(-1px);
    border-color: var(--border-strong);
}

.takeaway-number {
    display: flex; align-items: center; justify-content: center;
    width: 2rem; height: 2rem; flex-shrink: 0;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    color: #fff; font-size: 0.78rem; font-weight: 800;
}

.takeaway-text {
    font-size: 0.9rem; color: var(--text-secondary); line-height: 1.55;
    padding-top: 0.25rem;
}

/* Checklist tab */
.checklist-header {
    display: flex; justify-content: space-between; align-items: center;
    gap: 0.75rem;
    margin-bottom: 1rem;
}

.checklist-progress { flex: 1; }

.checklist-progress-bar {
    width: 100%; height: 0.5rem;
    border-radius: var(--radius-full);
    background: rgba(255,255,255,0.08);
    overflow: hidden; margin-bottom: 0.35rem;
}

.checklist-progress-fill {
    height: 100%;
    border-radius: inherit;
    background: linear-gradient(90deg, var(--primary), var(--success));
    transition: width 0.4s ease;
}

.checklist-progress-text {
    font-size: 0.78rem; font-weight: 600; color: var(--text-secondary);
}

.checklist-items { display: flex; flex-direction: column; gap: 0.35rem; }

.checklist-item {
    display: flex; align-items: center; gap: 0.75rem;
    padding: 0.85rem 1rem;
    border-radius: var(--radius-md);
    background: var(--card-bg);
    border: 1px solid var(--border);
    cursor: pointer;
    transition: all 0.2s ease;
}
.checklist-item:hover { background: var(--card-bg-hover); }

.checklist-checkbox {
    display: flex; align-items: center; justify-content: center;
    width: 1.5rem; height: 1.5rem; flex-shrink: 0;
    border-radius: 0.4rem;
    border: 2px solid var(--border-strong);
    background: transparent;
    transition: all 0.2s ease;
    color: transparent; font-size: 0.7rem;
}

.checklist-item.is-checked .checklist-checkbox {
    background: linear-gradient(135deg, var(--primary), var(--success));
    border-color: transparent;
    color: #fff;
}

.checklist-item.is-checked .checklist-text { text-decoration: line-through; color: var(--text-tertiary); }

.checklist-text { font-size: 0.88rem; color: var(--text-secondary); line-height: 1.5; flex: 1; }

.checklist-priority {
    font-size: 0.68rem; font-weight: 700;
    padding: 0.2rem 0.5rem;
    border-radius: var(--radius-full);
    text-transform: uppercase; letter-spacing: 0.03em;
    flex-shrink: 0;
}
.checklist-priority.high { background: rgba(239,68,68,0.15); color: #fca5a5; }
.checklist-priority.medium { background: rgba(245,158,11,0.15); color: #fcd34d; }
.checklist-priority.low { background: rgba(16,185,129,0.15); color: #6ee7b7; }

/* Revision plan tab */
.revision-plan { display: flex; flex-direction: column; gap: 0.75rem; }

.plan-day-card {
    padding: 1.1rem 1.25rem;
    border-radius: var(--radius-lg);
    background: var(--card-bg);
    border: 1px solid var(--border);
    transition: border-color 0.15s ease;
}
.plan-day-card:hover { border-color: var(--border-strong); }

.plan-day-header {
    display: flex; justify-content: space-between; align-items: center;
    margin-bottom: 0.65rem;
}

.plan-day-label {
    display: flex; align-items: center; gap: 0.5rem;
    font-weight: 800; font-size: 0.95rem;
}
.plan-day-label i { color: var(--accent); font-size: 0.85rem; }

.plan-day-duration {
    font-size: 0.78rem; font-weight: 600; color: var(--text-secondary);
    display: flex; align-items: center; gap: 0.35rem;
}
.plan-day-duration i { font-size: 0.72rem; }

.plan-day-focus {
    font-size: 0.88rem; font-weight: 600; color: var(--accent);
    margin-bottom: 0.5rem;
}

.plan-day-tasks { display: flex; flex-direction: column; gap: 0.3rem; margin-bottom: 0.6rem; }

.plan-day-task {
    display: flex; align-items: flex-start; gap: 0.5rem;
    font-size: 0.85rem; color: var(--text-secondary); line-height: 1.5;
    padding-left: 0.25rem;
}
.plan-day-task::before {
    content: '';
    display: inline-block;
    width: 0.35rem; height: 0.35rem; flex-shrink: 0;
    margin-top: 0.5rem;
    border-radius: 50%;
    background: var(--primary);
}

.plan-day-tip {
    font-size: 0.82rem; color: var(--text-tertiary);
    font-style: italic;
    padding: 0.6rem 0.8rem;
    border-radius: var(--radius-sm);
    background: rgba(79,70,229,0.06);
    border-left: 3px solid var(--primary);
}

/* Guide actions (save / print) */
.guide-actions {
    display: flex; gap: 0.6rem; flex-wrap: wrap;
    margin-top: 1.25rem;
    padding-top: 1rem;
    border-top: 1px solid var(--border);
}

/* ── Spinner ──────────────────────────────────────────────── */
.spinner {
    display: inline-block;
    width: 1.2rem; height: 1.2rem;
    border: 2px solid rgba(255,255,255,0.2);
    border-top-color: #fff;
    border-radius: 50%;
    animation: spin 0.6s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

/* ── 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;
}

/* ── Print styles ─────────────────────────────────────────── */
@media print {
    body::before, body::after, .workspace-header, .builder-drawer,
    .drawer-overlay, .session-toolbar,
    .guide-tabs, .guide-actions, .nav-container, .banner-container,
    footer { display: none !important; }

    body { background: #fff !important; color: #000 !important; }
    .glass-panel { background: none !important; border: none !important; box-shadow: none !important; backdrop-filter: none !important; padding: 0 !important; }
    .guide-tab-content { display: block !important; page-break-inside: avoid; margin-bottom: 2rem; }
    .guide-tab-content::before { content: attr(data-print-title); font-size: 1.3rem; font-weight: 800; display: block; margin-bottom: 0.5rem; border-bottom: 2px solid #000; padding-bottom: 0.3rem; }

    .section-card { display: flex !important; page-break-inside: avoid; }
    .stat-card, .coach-card, .takeaway-card, .checklist-item, .plan-day-card, .key-term-card { border: 1px solid #ddd !important; background: none !important; }
    .checklist-checkbox { border-color: #000 !important; }

    * { color: #000 !important; }
    .app-grid { display: block !important; }
    .study-shell { width: 100% !important; max-width: 100% !important; }
}

/* ── Responsive ───────────────────────────────────────────── */
@media (min-width: 860px) {
    .nav-links { display: flex; align-items: center; gap: 0.25rem; flex: 1; }
    .auth-buttons { display: flex; align-items: center; gap: 0.5rem; margin-left: auto; }
    .auth-buttons-mobile, .mobile-menu-button { display: none; }
}

@media (min-width: 1005px) {
    .workspace-header-shell { grid-template-columns: minmax(0, 1.25fr) minmax(300px, 0.8fr); }
    .overview-stats { grid-template-columns: repeat(4, 1fr); }
}

@media (max-width: 1004px) {
    .workspace-header-shell { grid-template-columns: 1fr; }
    .overview-stats { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 640px) {
    .field-grid-2 { grid-template-columns: 1fr; }
    .choice-grid { grid-template-columns: 1fr; }
    .hero-mini-grid { grid-template-columns: repeat(2, 1fr); }
    .plan-note { grid-template-columns: 1fr; }
    .guide-tab span { display: none; }
    .overview-stats { grid-template-columns: 1fr; }
    .section-key-terms { grid-template-columns: 1fr; }
    .guide-tabs { gap: 0.15rem; }
    .guide-tab { padding: 0.6rem 0.35rem; font-size: 0.75rem; }
}