/* ==========================================================================
   VibeAudio Design Foundation — Stage A
   Tactile Editorial Listening Sanctuary
   ========================================================================== */

:root {
    /* --- COLOR SYSTEM: WARM OBSIDIAN SANCTUARY --- */
    --color-canvas: #0C0D11;
    --color-surface-1: #16181F;
    --color-surface-2: #1E232B;
    --color-surface-3: #282E39;
    --color-surface-translucent: rgba(22, 24, 31, 0.88);
    --color-surface-overlay: rgba(12, 13, 17, 0.94);

    /* Text & Readability */
    --color-text-primary: #F5F6FA;
    --color-text-secondary: #9BA1B0;
    --color-text-soft: #C8CDD8;
    --color-text-dim: #6E7585;
    --color-text-muted: #545B6B;

    /* Semantic Accent (Warm Amber / Honey) */
    --color-accent: #E5A93C;
    --color-accent-hover: #F0B84D;
    --color-accent-active: #D49528;
    --color-accent-soft: rgba(229, 169, 60, 0.14);
    --color-accent-border: rgba(229, 169, 60, 0.28);
    --color-accent-glow: rgba(229, 169, 60, 0.16);

    /* Status & State Colors */
    --color-success: #4EBA87;
    --color-success-soft: rgba(78, 186, 135, 0.14);
    --color-success-border: rgba(78, 186, 135, 0.28);

    --color-warning: #E5A93C;
    --color-warning-soft: rgba(229, 169, 60, 0.14);
    --color-warning-border: rgba(229, 169, 60, 0.28);

    --color-danger: #E05D5D;
    --color-danger-soft: rgba(224, 93, 93, 0.14);
    --color-danger-border: rgba(224, 93, 93, 0.32);

    --color-info: #6E94B8;
    --color-info-soft: rgba(110, 148, 184, 0.14);

    /* Borders & Separators */
    --color-border: rgba(245, 246, 250, 0.07);
    --color-border-strong: rgba(245, 246, 250, 0.14);
    --color-border-subtle: rgba(245, 246, 250, 0.04);
    --color-divider: rgba(245, 246, 250, 0.06);

    /* Shadows */
    --shadow-subtle: 0 4px 12px rgba(0, 0, 0, 0.25);
    --shadow-card: 0 10px 28px rgba(0, 0, 0, 0.35);
    --shadow-elevated: 0 16px 40px rgba(0, 0, 0, 0.5);
    --shadow-sheet: 0 24px 60px rgba(0, 0, 0, 0.65);
    --shadow-focus: 0 0 0 3px rgba(229, 169, 60, 0.35);

    /* --- TYPOGRAPHY SYSTEM --- */
    --font-display: 'Newsreader', Georgia, 'Times New Roman', serif;
    --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-mono: 'JetBrains Mono', 'Fira Code', ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;

    /* --- SPACING SYSTEM (4/8/12/16/24/32/48) --- */
    --space-1: 4px;
    --space-2: 8px;
    --space-3: 12px;
    --space-4: 16px;
    --space-6: 24px;
    --space-8: 32px;
    --space-12: 48px;

    /* --- BORDER RADIUS SYSTEM --- */
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-card: 12px;
    --radius-panel: 16px;
    --radius-sheet: 22px;
    --radius-pill: 999px;

    /* --- MOTION TOKENS --- */
    --transition-fast: 150ms cubic-bezier(0.2, 0, 0, 1);
    --transition-base: 240ms cubic-bezier(0.2, 0, 0, 1);
    --transition-smooth: 350ms cubic-bezier(0.4, 0, 0.2, 1);

    /* --- SHELL & LAYOUT --- */
    --shell-width: 1200px;
    --nav-height: 70px;

    /* --- LEGACY COMPATIBILITY MAPPINGS --- */
    --primary: var(--color-accent);
    --secondary: var(--color-text-secondary);
    --accent-soft: var(--color-accent-soft);
    --dark-bg: var(--color-canvas);
    --glass-bg: rgba(245, 246, 250, 0.03);
    --text: var(--color-text-primary);
    --border: var(--color-border);
    --theme-bg-1: rgba(229, 169, 60, 0.08);
    --theme-bg-2: rgba(78, 186, 135, 0.05);
    --theme-bg-3: rgba(22, 24, 31, 0.4);
    --theme-bg-4: rgba(12, 13, 17, 0.995);
    --theme-surface-1: var(--color-surface-1);
    --theme-surface-2: rgba(245, 246, 250, 0.05);
    --theme-surface-3: rgba(245, 246, 250, 0.1);
    --theme-border: var(--color-border);
    --theme-border-strong: var(--color-border-strong);
    --theme-glow: var(--color-accent-glow);
    --theme-glow-soft: rgba(229, 169, 60, 0.06);
    --theme-shadow: var(--shadow-card);
    --theme-shadow-strong: var(--shadow-elevated);
    --theme-title: var(--color-text-primary);
    --theme-text: var(--color-text-primary);
    --theme-text-soft: var(--color-text-soft);
    --theme-text-dim: var(--color-text-dim);
    --theme-title-gradient-start: var(--color-text-primary);
    --theme-title-gradient-end: #E0CFA7;
    --theme-progress-track: rgba(245, 246, 250, 0.1);
    --theme-progress-fill: linear-gradient(90deg, #E5A93C, #F0C674);
    --theme-player-overlay: linear-gradient(135deg, rgba(229, 169, 60, 0.12), rgba(22, 24, 31, 0.6) 45%, rgba(12, 13, 17, 0.95));
}

/* --- RESET & ACCESSIBLE CORE --- */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: var(--font-body);
}

html {
    color-scheme: dark;
    scroll-behavior: smooth;
    background-color: var(--color-canvas);
}

body {
    color: var(--color-text-primary);
    min-height: 100vh;
    padding-bottom: 150px;
    overflow-x: hidden;
    position: relative;
    background-color: var(--color-canvas);
    background-image:
        radial-gradient(ellipse 70% 40% at 20% 0%, rgba(229, 169, 60, 0.06), transparent 60%),
        radial-gradient(ellipse 60% 30% at 80% 10%, rgba(78, 186, 135, 0.03), transparent 50%),
        linear-gradient(180deg, #0C0D11 0%, #090A0E 50%, #07080B 100%);
    background-attachment: fixed;
    font-size: 15px;
    line-height: 1.6;
    letter-spacing: -0.01em;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    transition: background 0.6s ease, color 0.4s ease;
}

body.player-mode {
    padding-bottom: 240px;
}

/* Subtle, calm ambient lighting layer */
body::before {
    content: "";
    position: fixed;
    inset: 0;
    pointer-events: none;
    z-index: -1;
    background: radial-gradient(circle at 50% 25%, rgba(229, 169, 60, 0.04) 0%, transparent 60%);
    opacity: 0.7;
}

/* --- ACCESSIBILITY & FOCUS --- */
button:focus-visible,
input:focus-visible,
a:focus-visible,
[tabindex="0"]:focus-visible,
.book-card:focus-visible,
.history-card:focus-visible {
    outline: 2px solid var(--color-accent);
    outline-offset: 3px;
    border-radius: inherit;
}

/* --- TACTILE MICRO-INTERACTIONS --- */
button,
.action-btn,
.ghost-btn,
.glass-btn,
.topbar-nav-btn,
.filter-btn,
.btn-secondary,
.popover-item-btn {
    -webkit-tap-highlight-color: transparent;
    user-select: none;
    -webkit-user-select: none;
}

button:active:not(:disabled),
.action-btn:active:not(:disabled),
.ghost-btn:active:not(:disabled),
.glass-btn:active:not(:disabled),
.topbar-nav-btn:active:not(:disabled),
.filter-btn:active:not(:disabled) {
    transform: scale(0.97);
}

/* --- SHELL CONTAINER --- */
.glass-container {
    max-width: var(--shell-width);
    margin: 0 auto;
    padding: 24px 28px 48px;
    position: relative;
}

/* --- TOPBAR & BRAND --- */
header,
.app-topbar {
    position: sticky;
    top: 14px;
    z-index: 120;
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 16px;
    margin-bottom: 28px;
    padding: 12px 20px;
    border-radius: var(--radius-sheet);
    background: var(--color-surface-translucent);
    border: 1px solid var(--color-border);
    box-shadow: var(--shadow-card);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    transition: background var(--transition-base), border var(--transition-base);
}

.topbar-left {
    display: flex;
    align-items: center;
    gap: 12px;
}

.brand-link {
    text-decoration: none;
    color: var(--color-text-primary);
    display: inline-block;
}

.brand-stack {
    display: grid;
    gap: 1px;
}

.brand-stack span,
.logo span {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    font-family: var(--font-display);
    font-size: clamp(1.35rem, 2vw, 1.65rem);
    font-weight: 600;
    letter-spacing: -0.02em;
    color: var(--color-text-primary);
}

.brand-stack span i,
.logo span i {
    color: var(--color-accent);
    font-size: 0.9em;
}

.brand-subtitle {
    color: var(--color-text-dim);
    font-size: 0.7rem;
    font-weight: 500;
    letter-spacing: 0.1em;
    text-transform: uppercase;
}

/* Primary Topbar Navigation (Desktop & Tablet) */
.topbar-nav {
    display: flex;
    align-items: center;
    gap: 6px;
    background: var(--color-surface-1);
    padding: 4px;
    border-radius: var(--radius-pill);
    border: 1px solid var(--color-border);
}

.topbar-nav-btn {
    background: transparent;
    border: none;
    color: var(--color-text-secondary);
    padding: 8px 16px;
    border-radius: var(--radius-pill);
    font-size: 0.84rem;
    font-weight: 600;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    transition: all var(--transition-fast);
}

.topbar-nav-btn:hover {
    color: var(--color-text-primary);
    background: var(--color-surface-2);
}

.topbar-nav-btn.active {
    background: var(--color-accent-soft);
    color: var(--color-accent);
    box-shadow: inset 0 0 0 1px var(--color-accent-border);
}

.topbar-right {
    display: flex;
    align-items: center;
    gap: 10px;
}

/* Search Bar */
.search-shell {
    display: flex;
    align-items: center;
    min-width: 220px;
}

.visually-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

.search-box {
    position: relative;
    width: 100%;
    min-height: 40px;
    padding: 0 14px;
    border-radius: var(--radius-pill);
    display: flex;
    align-items: center;
    gap: 8px;
    border: 1px solid var(--color-border);
    background: var(--color-surface-1);
    box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.03);
    transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.search-box i {
    color: var(--color-text-dim);
    font-size: 0.82rem;
}

.search-box input {
    width: 100%;
    background: transparent;
    border: none;
    color: var(--color-text-primary);
    font-size: 0.88rem;
    outline: none;
}

.search-box input::placeholder {
    color: var(--color-text-dim);
}

.search-box:focus-within {
    border-color: var(--color-accent-border);
    box-shadow: 0 0 0 1px var(--color-accent-soft), var(--shadow-subtle);
}

#search-clear-btn {
    position: absolute;
    right: 6px;
    top: 50%;
    transform: translateY(-50%);
    background: transparent;
    border: none;
    color: var(--color-text-dim);
    cursor: pointer;
    min-width: 28px;
    min-height: 28px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    transition: color var(--transition-fast), background var(--transition-fast);
}

#search-clear-btn:hover {
    color: var(--color-text-primary);
    background: rgba(255, 255, 255, 0.08);
}

/* Glass / Icon Buttons */
.glass-btn {
    background: var(--color-surface-1);
    border: 1px solid var(--color-border);
    color: var(--color-text-soft);
    width: 40px;
    height: 40px;
    border-radius: var(--radius-md);
    cursor: pointer;
    font-size: 0.95rem;
    display: inline-flex;
    justify-content: center;
    align-items: center;
    transition: background var(--transition-fast), color var(--transition-fast), border-color var(--transition-fast), transform var(--transition-fast);
    box-shadow: var(--shadow-subtle);
}

.glass-btn:hover {
    background: var(--color-surface-2);
    color: var(--color-text-primary);
    border-color: var(--color-border-strong);
    transform: translateY(-1px);
}

.glass-btn:active {
    transform: scale(0.96);
}

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

/* --- NAVIGATION DRAWER (SIDEBAR) --- */
#sidebar {
    position: fixed;
    top: 0;
    left: -320px;
    width: 300px;
    height: 100%;
    background: var(--color-surface-overlay);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-right: 1px solid var(--color-border);
    z-index: 2000;
    transition: left var(--transition-smooth);
    display: flex;
    flex-direction: column;
    box-shadow: var(--shadow-sheet);
}

#sidebar.active {
    left: 0;
}

#sidebar-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.65);
    z-index: 1999;
    backdrop-filter: blur(4px);
    -webkit-backdrop-filter: blur(4px);
    opacity: 0;
    visibility: hidden;
    transition: opacity var(--transition-base), visibility var(--transition-base);
}

#sidebar-overlay.active {
    opacity: 1;
    visibility: visible;
}

.sidebar-header {
    padding: 24px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px solid var(--color-divider);
}

.sidebar-header h3 {
    font-family: var(--font-display);
    font-size: 1.4rem;
    color: var(--color-text-primary);
    font-weight: 600;
}

#close-sidebar {
    background: transparent;
    border: none;
    color: var(--color-text-dim);
    font-size: 1.3rem;
    cursor: pointer;
    min-width: 44px;
    min-height: 44px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-md);
    transition: color var(--transition-fast), transform var(--transition-fast);
}

#close-sidebar:hover {
    color: var(--color-text-primary);
    transform: rotate(90deg);
}

.sidebar-nav {
    padding: 18px 16px;
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.sidebar-nav button {
    background: transparent;
    border: 1px solid transparent;
    color: var(--color-text-secondary);
    text-align: left;
    padding: 12px 16px;
    font-size: 0.95rem;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: background var(--transition-fast), color var(--transition-fast), border-color var(--transition-fast);
    display: flex;
    align-items: center;
    gap: 14px;
    font-weight: 500;
    min-height: 46px;
}

.sidebar-nav button:hover {
    background: var(--color-surface-2);
    color: var(--color-text-primary);
    border-color: var(--color-border);
}

.sidebar-nav button.active {
    background: var(--color-accent-soft);
    color: var(--color-accent);
    border-color: var(--color-accent-border);
}

.sidebar-nav button i {
    width: 22px;
    color: var(--color-text-dim);
    text-align: center;
    font-size: 1rem;
    transition: color var(--transition-fast);
}

.sidebar-nav button:hover i,
.sidebar-nav button.active i {
    color: var(--color-accent);
}

.divider {
    height: 1px;
    background: var(--color-divider);
    margin: 12px 0;
}

/* --- SECTION TYPOGRAPHY & HEADERS --- */
.section-header-row {
    display: flex;
    align-items: flex-end;
    justify-content: space-between;
    gap: 16px;
    margin-bottom: 22px;
}

.section-header-actions {
    display: flex;
    align-items: center;
    gap: 8px;
    flex-shrink: 0;
}

.section-title {
    font-family: var(--font-display);
    font-size: clamp(1.8rem, 3.2vw, 2.5rem);
    font-weight: 600;
    line-height: 1.1;
    letter-spacing: -0.025em;
    color: var(--color-text-primary);
    margin: 4px 0 8px;
}

.section-subtitle {
    color: var(--color-text-secondary);
    line-height: 1.6;
    max-width: 58ch;
    font-size: 0.95rem;
}

/* --- GRIDS & LAYOUT --- */
.grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
    gap: 22px;
}

.hidden {
    display: none !important;
}

.fade-in {
    animation: fadeIn var(--transition-base) ease-in-out;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(8px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* --- STATUS BANNERS --- */
.sync-status-banner,
.profile-sync-note {
    margin-top: 14px;
    padding: 10px 14px;
    border-radius: var(--radius-md);
    border: 1px solid var(--color-border);
    background: var(--color-surface-1);
    color: var(--color-text-secondary);
    line-height: 1.5;
    font-size: 0.85rem;
    display: flex;
    align-items: center;
    gap: 8px;
}

.sync-status-banner[data-status="synced"],
.profile-sync-note[data-status="synced"] {
    border-color: var(--color-success-border);
    background: var(--color-success-soft);
    color: var(--color-success);
}

.sync-status-banner[data-status="pending"],
.profile-sync-note[data-status="pending"] {
    border-color: var(--color-warning-border);
    background: var(--color-warning-soft);
    color: var(--color-warning);
}

.sync-status-banner[data-status="offline"],
.profile-sync-note[data-status="offline"] {
    border-color: var(--color-border-strong);
    background: var(--color-surface-2);
    color: var(--color-text-soft);
}

/* --- EMPTY STATES & LOADERS --- */
.empty-msg,
.empty-state {
    padding: 36px 24px;
    border-radius: var(--radius-panel);
    border: 1px dashed var(--color-border-strong);
    background: var(--color-surface-1);
    color: var(--color-text-secondary);
    text-align: center;
    font-size: 0.95rem;
}

.loading-spinner {
    padding: 28px;
    border-radius: var(--radius-panel);
    background: var(--color-surface-1);
    border: 1px solid var(--color-border);
    color: var(--color-accent);
    text-align: center;
    font-size: 0.95rem;
    animation: pulse 1.8s infinite ease-in-out;
}

@keyframes pulse {
    0%, 100% { opacity: 0.6; }
    50% { opacity: 1; }
}

/* --- TOAST NOTIFICATIONS --- */
.toast-msg {
    position: fixed;
    left: 50%;
    bottom: 24px;
    transform: translateX(-50%);
    padding: 11px 20px;
    border-radius: var(--radius-pill);
    background: var(--color-surface-3);
    color: var(--color-text-primary);
    border: 1px solid var(--color-border-strong);
    box-shadow: var(--shadow-sheet);
    z-index: 2200;
    font-size: 0.88rem;
    font-weight: 500;
    letter-spacing: -0.01em;
    pointer-events: none;
    animation: fadeIn var(--transition-fast) ease-out;
}

/* --- TABULAR NUMERALS --- */
.timestamp,
.timecode,
#current-time,
#total-duration,
.stat-box h3,
.insight-card strong {
    font-variant-numeric: tabular-nums;
    font-feature-settings: "tnum" 1;
}

/* --- PLAYER MODE OVERRIDES --- */
body.player-mode .app-topbar {
    background: transparent;
    border: none;
    box-shadow: none;
    backdrop-filter: none;
    -webkit-backdrop-filter: none;
    padding: 0;
    margin-bottom: 12px;
}

body.player-mode .brand-stack {
    justify-items: center;
}

body.player-mode .brand-subtitle {
    display: none;
}

body.player-mode .search-box,
body.player-mode .search-shell {
    display: none !important;
}

/* --- RESPONSIVE MEDIA QUERIES --- */
@media (max-width: 900px) {
    .topbar-nav {
        display: none;
    }

    .mobile-menu-btn {
        display: inline-flex;
    }

    .search-shell {
        min-width: 160px;
    }
}

@media (max-width: 768px) {
    body {
        padding-bottom: 120px;
        font-size: 14px;
    }

    .glass-container {
        padding: 12px 16px 36px;
    }

    .app-topbar {
        top: 8px;
        padding: 10px 14px;
        margin-bottom: 20px;
        border-radius: var(--radius-panel);
    }

    .brand-stack span,
    .logo span {
        font-size: 1.3rem;
    }

    .section-title {
        font-size: clamp(1.6rem, 5.5vw, 2rem);
        margin-bottom: 6px;
    }

    .grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
        gap: 12px;
    }

    body.player-mode {
        padding-bottom: 40px;
    }
}

@media (max-width: 350px) {
    .glass-container {
        padding: 8px 10px 28px;
    }

    .grid {
        grid-template-columns: 1fr;
        gap: 12px;
    }
}

/* --- REDUCED MOTION --- */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }
}

/* --- PWA STANDALONE & SAFE AREA INSETS --- */
@supports (padding-top: env(safe-area-inset-top)) {
    body {
        padding-top: env(safe-area-inset-top, 0px);
        padding-bottom: env(safe-area-inset-bottom, 0px);
        padding-left: env(safe-area-inset-left, 0px);
        padding-right: env(safe-area-inset-right, 0px);
    }

    body.is-standalone-app .app-topbar,
    @media (display-mode: standalone) {
        .app-topbar {
            top: max(8px, env(safe-area-inset-top, 8px));
        }

        .landing-topbar {
            padding-top: max(16px, env(safe-area-inset-top, 16px));
        }
    }
}

body.is-standalone-app #install-app-btn,
body.is-standalone-app [data-install-btn],
@media (display-mode: standalone) {
    #install-app-btn,
    [data-install-btn] {
        display: none !important;
    }
}