/* ============================================================
   A2Z DSA TRACKER — Design System
   Dark mode default, Light mode toggle
   ============================================================ */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800;900&display=swap');

/* ── CSS Custom Properties ── */
:root {
    /* Shared */
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 20px;
    --radius-full: 9999px;
    --transition-fast: 150ms ease;
    --transition-normal: 300ms ease;
    --transition-slow: 500ms ease;
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.12);
    --shadow-md: 0 4px 12px rgba(0,0,0,0.15);
    --shadow-lg: 0 8px 30px rgba(0,0,0,0.2);
    --shadow-glow: 0 0 20px rgba(16, 185, 129, 0.15);

    /* Difficulty */
    --easy-color: #10b981;
    --medium-color: #f59e0b;
    --hard-color: #ef4444;

    /* Accent */
    --accent: #10b981;
    --accent-hover: #34d399;
    --accent-glow: rgba(16, 185, 129, 0.25);
    --accent-subtle: rgba(16, 185, 129, 0.08);
}

/* ── Dark Theme (Default) ── */
[data-theme="dark"] {
    --bg-primary: #0d1117;
    --bg-secondary: #161b22;
    --bg-tertiary: #1c2333;
    --bg-card: #1c2333;
    --bg-card-hover: #222d3f;
    --bg-input: #0d1117;
    --bg-table-header: #131922;
    --bg-table-row-hover: rgba(16, 185, 129, 0.04);
    --bg-completed-row: rgba(16, 185, 129, 0.06);

    --border-primary: #30363d;
    --border-subtle: #21262d;
    --border-accent: rgba(16, 185, 129, 0.3);

    --text-primary: #e6edf3;
    --text-secondary: #8b949e;
    --text-tertiary: #6e7681;
    --text-link: #58a6ff;
    --text-completed: #34d399;

    --collapsible-bg: #1a2744;
    --collapsible-hover: #22345a;
    --collapsible-complete: #064e3b;
    --collapsible-complete-hover: #065f46;

    --progress-bar: var(--accent);
    --scrollbar-thumb: #30363d;
    --scrollbar-track: #0d1117;

    --glass-bg: rgba(22, 27, 34, 0.7);
    --glass-border: rgba(48, 54, 61, 0.6);

    --toast-bg: #1c2333;
    --toast-border: var(--accent);

    color-scheme: dark;
}

/* ── Light Theme ── */
[data-theme="light"] {
    --bg-primary: #f6f8fa;
    --bg-secondary: #ffffff;
    --bg-tertiary: #f0f3f6;
    --bg-card: #ffffff;
    --bg-card-hover: #f6f8fa;
    --bg-input: #f6f8fa;
    --bg-table-header: #f0f3f6;
    --bg-table-row-hover: rgba(16, 185, 129, 0.04);
    --bg-completed-row: rgba(16, 185, 129, 0.06);

    --border-primary: #d0d7de;
    --border-subtle: #e8ecf0;
    --border-accent: rgba(16, 185, 129, 0.3);

    --text-primary: #1f2328;
    --text-secondary: #57606a;
    --text-tertiary: #8b949e;
    --text-link: #0969da;
    --text-completed: #059669;

    --collapsible-bg: #2c5282;
    --collapsible-hover: #3b6aaa;
    --collapsible-complete: #059669;
    --collapsible-complete-hover: #10b981;

    --progress-bar: var(--accent);
    --scrollbar-thumb: #d0d7de;
    --scrollbar-track: #f6f8fa;

    --glass-bg: rgba(255, 255, 255, 0.8);
    --glass-border: rgba(208, 215, 222, 0.6);

    --toast-bg: #ffffff;
    --toast-border: var(--accent);

    color-scheme: light;
}

/* ── Reset & Base ── */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    font-size: 16px;
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family);
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    transition: background-color var(--transition-normal), color var(--transition-normal);
    overflow-x: hidden;
}

/* Scrollbar */
::-webkit-scrollbar { width: 8px; height: 8px; }
::-webkit-scrollbar-track { background: var(--scrollbar-track); }
::-webkit-scrollbar-thumb { background: var(--scrollbar-thumb); border-radius: 4px; }
::-webkit-scrollbar-thumb:hover { background: var(--text-tertiary); }

/* ── Header ── */
.app-header {
    position: sticky;
    top: 0;
    z-index: 100;
    background: var(--glass-bg);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border-bottom: 1px solid var(--border-subtle);
    padding: 0.75rem 1.5rem;
    transition: background var(--transition-normal), border var(--transition-normal);
}

.header-inner {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
}

.header-left {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.app-logo {
    font-size: 1.25rem;
    font-weight: 800;
    letter-spacing: -0.5px;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.app-logo .dot {
    color: var(--accent);
}

.global-progress {
    font-size: 0.85rem;
    color: var(--text-secondary);
    background: var(--accent-subtle);
    padding: 0.25rem 0.75rem;
    border-radius: var(--radius-full);
    font-weight: 600;
    border: 1px solid var(--border-accent);
    white-space: nowrap;
}

.global-progress .count {
    color: var(--accent);
    font-weight: 700;
}

.header-right {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

/* Theme Toggle */
.theme-toggle {
    position: relative;
    width: 52px;
    height: 28px;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-full);
    cursor: pointer;
    transition: background var(--transition-fast);
    display: flex;
    align-items: center;
    padding: 0 3px;
}

.theme-toggle:hover {
    border-color: var(--accent);
}

.theme-toggle-knob {
    width: 22px;
    height: 22px;
    background: var(--accent);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 12px;
    transition: transform var(--transition-normal);
    box-shadow: 0 1px 4px rgba(0,0,0,0.2);
}

[data-theme="light"] .theme-toggle-knob {
    transform: translateX(24px);
}

/* Auth Buttons */
.auth-btn {
    display: flex;
    align-items: center;
    gap: 0.45rem;
    padding: 0.35rem 0.85rem;
    border-radius: var(--radius-full);
    border: 1px solid var(--border-primary);
    background: var(--bg-tertiary);
    color: var(--text-primary);
    cursor: pointer;
    font-size: 0.8rem;
    font-weight: 500;
    font-family: var(--font-family);
    transition: all var(--transition-fast);
    white-space: nowrap;
}

.auth-btn:hover {
    border-color: var(--accent);
    background: var(--accent-subtle);
}

.auth-btn svg {
    width: 16px;
    height: 16px;
}

.auth-btn.signed-in {
    border-color: var(--accent);
    background: var(--accent-subtle);
}

.auth-avatar {
    width: 22px;
    height: 22px;
    border-radius: 50%;
    border: 1px solid var(--accent);
}



/* ── Hero Stats ── */
.hero-section {
    max-width: 1200px;
    margin: 1.5rem auto 0;
    padding: 0 1.5rem;
}

.hero-title {
    text-align: center;
    margin-bottom: 1.5rem;
}

.hero-title h1 {
    font-size: 2.5rem;
    font-weight: 900;
    letter-spacing: -1px;
    background: linear-gradient(135deg, var(--accent), #3b82f6);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-title p {
    color: var(--text-secondary);
    font-size: 1rem;
    margin-top: 0.25rem;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 1rem;
    margin-bottom: 1.5rem;
}

.stat-card {
    background: var(--glass-bg);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-lg);
    padding: 1.25rem;
    text-align: center;
    transition: all var(--transition-normal);
    position: relative;
    overflow: hidden;
}

.stat-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--accent), #3b82f6);
    opacity: 0;
    transition: opacity var(--transition-normal);
}

.stat-card:hover {
    transform: translateY(-2px);
    border-color: var(--border-accent);
    box-shadow: var(--shadow-glow);
}

.stat-card:hover::before {
    opacity: 1;
}

.stat-icon {
    font-size: 1.5rem;
    margin-bottom: 0.4rem;
}

.stat-value {
    font-size: 1.75rem;
    font-weight: 800;
    color: var(--text-primary);
    letter-spacing: -0.5px;
    line-height: 1.2;
}

.stat-label {
    font-size: 0.75rem;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    font-weight: 600;
    margin-top: 0.25rem;
}

/* ── Search ── */
.search-wrapper {
    max-width: 1200px;
    margin: 0 auto 1.5rem;
    padding: 0 1.5rem;
}

.search-container {
    position: relative;
}

.search-input {
    width: 100%;
    padding: 0.85rem 1rem 0.85rem 2.75rem;
    background: var(--bg-secondary);
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    font-size: 0.95rem;
    font-family: var(--font-family);
    transition: all var(--transition-fast);
    outline: none;
}

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

.search-input:focus {
    border-color: var(--accent);
    box-shadow: 0 0 0 3px var(--accent-glow);
}

.search-icon {
    position: absolute;
    left: 0.9rem;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-tertiary);
    width: 18px;
    height: 18px;
}

.search-shortcut {
    position: absolute;
    right: 0.9rem;
    top: 50%;
    transform: translateY(-50%);
    display: flex;
    gap: 0.25rem;
}

.search-shortcut kbd {
    background: var(--bg-tertiary);
    border: 1px solid var(--border-primary);
    border-radius: 4px;
    padding: 0.1rem 0.4rem;
    font-size: 0.7rem;
    color: var(--text-tertiary);
    font-family: var(--font-family);
}

/* ── Filter Bar ── */
.filter-bar {
    max-width: 1200px;
    margin: 0 auto 1.25rem;
    padding: 0 1.5rem;
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.filter-btn {
    padding: 0.45rem 1.1rem;
    border-radius: var(--radius-full);
    border: 1px solid var(--border-primary);
    background: var(--bg-secondary);
    color: var(--text-secondary);
    font-size: 0.82rem;
    font-weight: 600;
    font-family: var(--font-family);
    cursor: pointer;
    transition: all var(--transition-fast);
    white-space: nowrap;
}

.filter-btn:hover {
    border-color: var(--accent);
    color: var(--text-primary);
    background: var(--accent-subtle);
}

.filter-btn.active {
    background: var(--accent);
    border-color: var(--accent);
    color: #fff;
    box-shadow: 0 2px 8px var(--accent-glow);
}

/* ── Revision Star ── */
.revision-cell {
    cursor: pointer;
    text-align: center;
}

.revision-star {
    font-size: 1.2rem;
    color: var(--text-tertiary);
    opacity: 0.35;
    cursor: pointer;
    transition: all var(--transition-fast);
    display: inline-block;
    user-select: none;
}

.revision-star:hover {
    opacity: 0.7;
    transform: scale(1.2);
}

.revision-star.active {
    color: #f59e0b;
    opacity: 1;
    filter: drop-shadow(0 0 4px rgba(245, 158, 11, 0.4));
}

.revision-star.active:hover {
    transform: scale(1.25);
}

tr.starred .revision-star {
    color: #f59e0b;
    opacity: 1;
}

/* ── Main Content ── */
.main-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem 3rem;
}

/* ── Collapsible Sections ── */
.step-section {
    margin-bottom: 0.75rem;
}

.collapsible,
.sub-collapsible {
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0.9rem 1.25rem;
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    color: #fff;
    font-family: var(--font-family);
    font-weight: 600;
    position: relative;
    overflow: hidden;
    z-index: 1;
    background: var(--collapsible-bg);
    transition: background var(--transition-fast), transform var(--transition-fast), box-shadow var(--transition-fast);
    text-align: left;
    outline: none;
}

.collapsible {
    font-size: 1.1rem;
    margin-bottom: 0.5rem;
}

.sub-collapsible {
    font-size: 0.95rem;
    margin-bottom: 0.35rem;
}

.collapsible:hover,
.sub-collapsible:hover {
    background: var(--collapsible-hover);
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.collapsible.completed,
.sub-collapsible.completed {
    background: var(--collapsible-complete);
}

.collapsible.completed:hover,
.sub-collapsible.completed:hover {
    background: var(--collapsible-complete-hover);
}

/* Progress Bar inside collapsible */
.collapsible::before,
.sub-collapsible::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    height: 100%;
    width: var(--progress-width, 0%);
    background: var(--progress-bar);
    opacity: 0.2;
    transition: width 0.4s ease-out;
    z-index: 1;
}

.collapsible-title {
    flex-grow: 1;
    position: relative;
    z-index: 2;
}

.progress-counter {
    font-size: 0.75em;
    font-weight: 500;
    background: rgba(0, 0, 0, 0.25);
    padding: 0.2rem 0.65rem;
    border-radius: var(--radius-full);
    margin-left: 0.75rem;
    white-space: nowrap;
    position: relative;
    z-index: 2;
}

.collapse-icon {
    margin-left: 0.75rem;
    transition: transform var(--transition-normal);
    position: relative;
    z-index: 2;
    font-size: 0.8em;
    flex-shrink: 0;
}

.collapsible.active .collapse-icon,
.sub-collapsible.active .collapse-icon {
    transform: rotate(180deg);
}

/* Content panels */
.content,
.sub-content {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.4s ease-in-out;
}

.content {
    padding: 0 0.25rem;
}

.sub-content {
    padding: 0 0.15rem;
}

/* ── Question Table ── */
.table-container {
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    margin: 0.5rem 0 0.75rem;
    border-radius: var(--radius-md);
    border: 1px solid var(--border-primary);
}

table {
    width: 100%;
    border-collapse: collapse;
    min-width: 700px;
    table-layout: fixed;
}

thead th {
    background: var(--bg-table-header);
    color: var(--text-secondary);
    font-weight: 600;
    font-size: 0.78rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    padding: 0.65rem 0.5rem;
    border-bottom: 1px solid var(--border-primary);
    position: sticky;
    top: 0;
    z-index: 5;
}

td {
    padding: 0.5rem;
    border-bottom: 1px solid var(--border-subtle);
    vertical-align: middle;
    text-align: center;
    font-size: 0.9rem;
    color: var(--text-secondary);
    transition: background var(--transition-fast);
}

.topic-cell {
    text-align: left;
    width: 34%;
    font-weight: 500;
    color: var(--text-primary);
}

thead th:not(:first-child),
tbody td:not(.topic-cell) {
    width: 9.4%;
}

tr {
    transition: background var(--transition-fast);
}

tr:hover {
    background: var(--bg-table-row-hover);
}

/* Difficulty indicators */
tr.difficulty-easy .topic-cell {
    border-left: 4px solid var(--easy-color);
}

tr.difficulty-medium .topic-cell {
    border-left: 4px solid var(--medium-color);
}

tr.difficulty-hard .topic-cell {
    border-left: 4px solid var(--hard-color);
}

/* Completed row */
tr.completed {
    background: var(--bg-completed-row) !important;
}

tr.completed .topic-cell {
    color: var(--text-completed);
    text-decoration: line-through;
    text-decoration-color: rgba(16, 185, 129, 0.3);
}

tr.completed a {
    color: var(--text-completed) !important;
}

/* Topic title */
.topic-title {
    padding: 0.25rem 0.5rem;
    font-size: 0.9rem;
}

/* Link cells */
.link-cell {
    cursor: pointer;
    transition: background var(--transition-fast);
}

.link-cell:hover {
    background: var(--bg-card-hover);
}

.link-cell a {
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 0.35rem;
    color: var(--text-link);
    text-decoration: none;
}

.link-cell img {
    width: 22px;
    height: 22px;
    opacity: 0.8;
    transition: opacity var(--transition-fast), transform var(--transition-fast);
}

.link-cell:hover img {
    opacity: 1;
    transform: scale(1.15);
}

.na-cell {
    color: var(--text-tertiary);
    font-size: 0.85rem;
}

/* Checkbox */
.status-cell {
    cursor: pointer;
}

.status-checkbox {
    -webkit-appearance: none;
    appearance: none;
    width: 1.2em;
    height: 1.2em;
    border: 2px solid var(--text-tertiary);
    border-radius: 4px;
    background: transparent;
    cursor: pointer;
    display: grid;
    place-content: center;
    pointer-events: none;
    transition: all var(--transition-fast);
}

.status-checkbox::before {
    content: "";
    width: 0.65em;
    height: 0.65em;
    clip-path: polygon(14% 44%, 0 65%, 50% 100%, 100% 16%, 80% 0%, 43% 62%);
    transform: scale(0);
    transition: transform 150ms ease-in-out;
    background: #fff;
}

.status-checkbox:checked {
    background: var(--accent);
    border-color: var(--accent);
}

.status-checkbox:checked::before {
    transform: scale(1);
}

/* ── Celebration Animations ── */

/* Celebration overlay */
.celebration-container {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 9999;
    overflow: hidden;
}

/* Confetti particle */
.confetti {
    position: absolute;
    width: 10px;
    height: 10px;
    animation: confetti-fall 1.5s ease-out forwards;
}

@keyframes confetti-fall {
    0% {
        transform: translateY(0) rotate(0deg) scale(1);
        opacity: 1;
    }
    100% {
        transform: translateY(100vh) rotate(720deg) scale(0.3);
        opacity: 0;
    }
}

/* Emoji rain */
.emoji-particle {
    position: absolute;
    font-size: 1.5rem;
    animation: emoji-rain 2s ease-out forwards;
}

@keyframes emoji-rain {
    0% {
        transform: translateY(-50px) scale(0.5) rotate(0deg);
        opacity: 1;
    }
    100% {
        transform: translateY(100vh) scale(1.2) rotate(360deg);
        opacity: 0;
    }
}

/* Pulse ring */
.pulse-ring {
    position: absolute;
    width: 30px;
    height: 30px;
    border-radius: 50%;
    border: 3px solid var(--accent);
    animation: pulse-expand 0.8s ease-out forwards;
}

@keyframes pulse-expand {
    0% {
        transform: scale(0.5);
        opacity: 1;
    }
    100% {
        transform: scale(8);
        opacity: 0;
    }
}

/* Star burst */
.star-particle {
    position: absolute;
    font-size: 1.2rem;
    animation: star-burst 1s ease-out forwards;
}

@keyframes star-burst {
    0% {
        transform: translate(0, 0) scale(0.3);
        opacity: 1;
    }
    100% {
        opacity: 0;
    }
}

/* Checkmark zoom */
.checkmark-zoom {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%) scale(0);
    font-size: 5rem;
    animation: checkmark-anim 0.8s ease-out forwards;
    z-index: 10000;
    pointer-events: none;
}

@keyframes checkmark-anim {
    0% { transform: translate(-50%, -50%) scale(0) rotate(-45deg); opacity: 0; }
    40% { transform: translate(-50%, -50%) scale(1.2) rotate(10deg); opacity: 1; }
    70% { transform: translate(-50%, -50%) scale(0.9) rotate(-5deg); opacity: 1; }
    100% { transform: translate(-50%, -50%) scale(0) rotate(0deg); opacity: 0; }
}

/* Sparkle */
.sparkle {
    position: absolute;
    width: 6px;
    height: 6px;
    background: var(--accent);
    border-radius: 50%;
    animation: sparkle-rise 1.2s ease-out forwards;
}

@keyframes sparkle-rise {
    0% {
        transform: translateY(0) scale(1);
        opacity: 1;
        box-shadow: 0 0 6px var(--accent);
    }
    100% {
        transform: translateY(-150px) scale(0);
        opacity: 0;
        box-shadow: 0 0 20px var(--accent);
    }
}

/* Trophy */
.trophy-flash {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%) scale(0);
    font-size: 4rem;
    animation: trophy-anim 1.2s ease-out forwards;
    z-index: 10000;
    pointer-events: none;
}

@keyframes trophy-anim {
    0% { transform: translate(-50%, -50%) scale(0) rotate(-30deg); opacity: 0; }
    25% { transform: translate(-50%, -50%) scale(1.3) rotate(5deg); opacity: 1; }
    50% { transform: translate(-50%, -50%) scale(1) rotate(-2deg); opacity: 1; }
    80% { transform: translate(-50%, -50%) scale(1.1) rotate(0deg); opacity: 1; }
    100% { transform: translate(-50%, -50%) scale(0) rotate(15deg); opacity: 0; }
}

/* Wave ripple */
.wave-ripple {
    position: absolute;
    border-radius: 50%;
    background: var(--accent);
    animation: wave-anim 1s ease-out forwards;
}

@keyframes wave-anim {
    0% {
        transform: scale(0);
        opacity: 0.5;
    }
    100% {
        transform: scale(15);
        opacity: 0;
    }
}

/* Toast notification */
.toast {
    position: fixed;
    top: 5rem;
    left: 50%;
    transform: translateX(-50%) translateY(-120%);
    background: var(--toast-bg);
    border: 1px solid var(--toast-border);
    border-radius: var(--radius-md);
    padding: 1rem 2rem;
    z-index: 10001;
    text-align: center;
    box-shadow: var(--shadow-lg);
    animation: toast-slide 3s ease forwards;
    pointer-events: none;
}

.toast h3 {
    color: var(--accent);
    font-size: 1.1rem;
    margin-bottom: 0.25rem;
}

.toast p {
    color: var(--text-secondary);
    font-size: 0.85rem;
}

@keyframes toast-slide {
    0% { transform: translateX(-50%) translateY(-120%); opacity: 0; }
    15% { transform: translateX(-50%) translateY(0); opacity: 1; }
    75% { transform: translateX(-50%) translateY(0); opacity: 1; }
    100% { transform: translateX(-50%) translateY(-120%); opacity: 0; }
}

/* Big celebration banner */
.level-up-banner {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 10002;
    pointer-events: none;
    animation: banner-anim 3s ease forwards;
}

.level-up-banner .banner-content {
    text-align: center;
    animation: banner-scale 3s ease forwards;
}

.level-up-banner h2 {
    font-size: 3rem;
    font-weight: 900;
    background: linear-gradient(135deg, #10b981, #3b82f6, #8b5cf6);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.level-up-banner p {
    font-size: 1.2rem;
    color: var(--text-secondary);
    margin-top: 0.5rem;
}

@keyframes banner-anim {
    0% { background: transparent; }
    10% { background: rgba(0,0,0,0.4); }
    70% { background: rgba(0,0,0,0.4); }
    100% { background: transparent; }
}

@keyframes banner-scale {
    0% { transform: scale(0) rotate(-10deg); opacity: 0; }
    15% { transform: scale(1.1) rotate(2deg); opacity: 1; }
    25% { transform: scale(1) rotate(0deg); opacity: 1; }
    75% { transform: scale(1) rotate(0deg); opacity: 1; }
    100% { transform: scale(0.8) rotate(5deg); opacity: 0; }
}

/* Screen flash for mega celebrations */
.screen-flash {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--accent);
    z-index: 9998;
    pointer-events: none;
    animation: flash-anim 0.6s ease-out forwards;
}

@keyframes flash-anim {
    0% { opacity: 0.3; }
    100% { opacity: 0; }
}

/* ── Search Results Highlight ── */
.search-highlight {
    display: block !important;
}

.search-hidden {
    display: none !important;
}

tr.search-match {
    background: var(--accent-subtle) !important;
    border-left: 3px solid var(--accent);
}

/* ── No Results ── */
.no-results {
    text-align: center;
    padding: 3rem 1rem;
    color: var(--text-tertiary);
    font-size: 1.1rem;
}

.no-results span {
    font-size: 2.5rem;
    display: block;
    margin-bottom: 0.5rem;
}

/* ── Auth Modal ── */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(4px);
    z-index: 10000;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-normal);
}

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

.modal {
    background: var(--bg-secondary);
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-xl);
    padding: 2rem;
    max-width: 420px;
    width: 90%;
    box-shadow: var(--shadow-lg);
    transform: scale(0.9) translateY(20px);
    transition: transform var(--transition-normal);
}

.modal-overlay.active .modal {
    transform: scale(1) translateY(0);
}

.modal h2 {
    font-size: 1.25rem;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

.modal p {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-bottom: 1.5rem;
}

.modal-close {
    position: absolute;
    top: 1rem;
    right: 1rem;
    background: none;
    border: none;
    color: var(--text-tertiary);
    cursor: pointer;
    font-size: 1.25rem;
}

.google-signin-btn {
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.75rem;
    padding: 0.75rem 1.25rem;
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-md);
    background: var(--bg-tertiary);
    color: var(--text-primary);
    font-size: 0.95rem;
    font-weight: 500;
    font-family: var(--font-family);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.google-signin-btn:hover {
    border-color: var(--accent);
    background: var(--accent-subtle);
}

.google-signin-btn img {
    width: 20px;
    height: 20px;
}

.modal-actions {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.modal-divider {
    display: flex;
    align-items: center;
    gap: 1rem;
    color: var(--text-tertiary);
    font-size: 0.8rem;
}

.modal-divider::before,
.modal-divider::after {
    content: '';
    flex: 1;
    height: 1px;
    background: var(--border-primary);
}

.export-import-row {
    display: flex;
    gap: 0.75rem;
}

.export-import-row button {
    flex: 1;
    padding: 0.6rem;
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-md);
    background: var(--bg-tertiary);
    color: var(--text-primary);
    font-size: 0.85rem;
    font-weight: 500;
    font-family: var(--font-family);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.export-import-row button:hover {
    border-color: var(--accent);
    background: var(--accent-subtle);
}

/* ── Responsive ── */

@media (max-width: 768px) {
    html { font-size: 14px; }

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

    .header-inner {
        flex-wrap: wrap;
    }

    .hero-title h1 {
        font-size: 2rem;
    }

    .collapsible {
        font-size: 1rem;
        padding: 0.75rem 1rem;
    }

    .sub-collapsible {
        font-size: 0.9rem;
        padding: 0.65rem 0.9rem;
    }

    .search-shortcut { display: none; }
}

@media (max-width: 480px) {
    html { font-size: 13px; }

    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 0.5rem;
    }

    .stat-card {
        padding: 0.85rem;
    }

    .stat-value {
        font-size: 1.4rem;
    }

    .hero-title h1 {
        font-size: 1.6rem;
    }

    .app-logo {
        font-size: 1rem;
    }

    .global-progress {
        font-size: 0.75rem;
        padding: 0.15rem 0.5rem;
    }

    .collapsible {
        font-size: 0.9rem;
    }

    .sub-collapsible {
        font-size: 0.85rem;
    }

    .auth-btn span {
        display: none;
    }
}

/* ── Utility ── */
.hidden { display: none !important; }
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    overflow: hidden;
    clip: rect(0,0,0,0);
    white-space: nowrap;
    border: 0;
}

/* ── Loading State ── */
.loading-skeleton {
    background: linear-gradient(90deg, var(--bg-tertiary) 25%, var(--bg-card-hover) 50%, var(--bg-tertiary) 75%);
    background-size: 200% 100%;
    animation: skeleton-shimmer 1.5s infinite;
    border-radius: var(--radius-md);
    height: 48px;
    margin-bottom: 0.5rem;
}

@keyframes skeleton-shimmer {
    0% { background-position: 200% 0; }
    100% { background-position: -200% 0; }
}