/* ============================================================
   SuperBrain Academy — Main Stylesheet
   Designed for a 10-year-old girl with ADHD.
   Mobile-first, high contrast, warm & encouraging.
   ============================================================ */

/* ----------------------------------------------------------
   CSS Custom Properties (Design Tokens)
   ---------------------------------------------------------- */
:root {
    --color-bg:        #FFF8F0;
    --color-primary:   #FF6B6B;
    --color-primary-dark: #e85555;
    --color-secondary: #4ECDC4;
    --color-secondary-dark: #3ab8b0;
    --color-accent:    #FFE66D;
    --color-success:   #34D399;
    --color-text:      #2D3436;
    --color-text-muted: #636e72;
    --color-white:     #FFFFFF;
    --color-card-bg:   #FFFFFF;
    --color-locked:    #b2bec3;

    --font-main: 'Nunito', 'Segoe UI', sans-serif;

    --radius-sm:  8px;
    --radius-md:  16px;
    --radius-lg:  24px;
    --radius-xl:  32px;
    --radius-full: 9999px;

    --shadow-sm:  0 2px 8px rgba(0,0,0,.08);
    --shadow-md:  0 4px 20px rgba(0,0,0,.12);
    --shadow-lg:  0 8px 40px rgba(0,0,0,.16);

    --transition: .2s ease;
}

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

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

body {
    font-family: var(--font-main);
    background-color: var(--color-bg);
    color: var(--color-text);
    min-height: 100vh;
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

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

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

button {
    font-family: var(--font-main);
    cursor: pointer;
    border: none;
    outline: none;
}

/* ----------------------------------------------------------
   Utility Classes
   ---------------------------------------------------------- */
.sr-only {
    position: absolute;
    width: 1px; height: 1px;
    padding: 0; margin: -1px;
    overflow: hidden;
    clip: rect(0,0,0,0);
    white-space: nowrap;
    border: 0;
}

.text-center { text-align: center; }
.mt-1  { margin-top: .5rem; }
.mt-2  { margin-top: 1rem; }
.mt-3  { margin-top: 1.5rem; }
.mb-1  { margin-bottom: .5rem; }
.mb-2  { margin-bottom: 1rem; }

/* ----------------------------------------------------------
   Site Footer
   ---------------------------------------------------------- */
.site-footer {
    text-align: center;
    padding: 1.5rem;
    font-size: .85rem;
    color: var(--color-text-muted);
    margin-top: 3rem;
}

/* ----------------------------------------------------------
   Buttons
   ---------------------------------------------------------- */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: .5rem;
    padding: .75rem 1.75rem;
    border-radius: var(--radius-full);
    font-size: 1rem;
    font-weight: 700;
    transition: transform var(--transition), box-shadow var(--transition), background-color var(--transition);
    min-height: 44px; /* accessibility: min touch target */
    touch-action: manipulation;
}

.btn:active {
    transform: scale(.96);
}

.btn-primary {
    background: var(--color-primary);
    color: var(--color-white);
    box-shadow: 0 4px 15px rgba(255,107,107,.4);
}
.btn-primary:hover {
    background: var(--color-primary-dark);
    box-shadow: 0 6px 20px rgba(255,107,107,.5);
    transform: translateY(-2px);
}

.btn-secondary {
    background: var(--color-secondary);
    color: var(--color-white);
    box-shadow: 0 4px 15px rgba(78,205,196,.4);
}
.btn-secondary:hover {
    background: var(--color-secondary-dark);
    transform: translateY(-2px);
}

.btn-accent {
    background: var(--color-accent);
    color: var(--color-text);
    box-shadow: 0 4px 15px rgba(255,230,109,.4);
}
.btn-accent:hover {
    filter: brightness(.95);
    transform: translateY(-2px);
}

.btn-ghost {
    background: transparent;
    color: var(--color-text-muted);
    border: 2px solid #dfe6e9;
}
.btn-ghost:hover {
    border-color: var(--color-primary);
    color: var(--color-primary);
}

.btn-lg {
    padding: 1rem 2.5rem;
    font-size: 1.15rem;
}

.btn-sm {
    padding: .5rem 1.25rem;
    font-size: .9rem;
}

/* ----------------------------------------------------------
   Top Navigation Bar (child pages)
   ---------------------------------------------------------- */
.topbar {
    background: var(--color-white);
    box-shadow: var(--shadow-sm);
    padding: .75rem 1.25rem;
    display: flex;
    align-items: center;
    gap: 1rem;
    position: sticky;
    top: 0;
    z-index: 100;
}

.topbar__avatar {
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--color-primary), var(--color-accent));
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    flex-shrink: 0;
}

.topbar__name {
    font-size: 1rem;
    font-weight: 800;
    color: var(--color-text);
    flex: 1;
}

.topbar__stats {
    display: flex;
    gap: .75rem;
    align-items: center;
    flex-wrap: wrap;
}

.topbar__stat {
    display: flex;
    align-items: center;
    gap: .3rem;
    font-weight: 700;
    font-size: .9rem;
    background: var(--color-bg);
    padding: .3rem .75rem;
    border-radius: var(--radius-full);
}

.topbar__stat--level  { color: var(--color-primary); }
.topbar__stat--stars  { color: #f39c12; }
.topbar__stat--streak { color: #e17055; }

.topbar__logout {
    background: none;
    color: var(--color-text-muted);
    font-size: .85rem;
    font-weight: 600;
    padding: .4rem .9rem;
    border-radius: var(--radius-full);
    border: 2px solid #dfe6e9;
    transition: var(--transition);
}
.topbar__logout:hover {
    border-color: var(--color-primary);
    color: var(--color-primary);
}

/* ----------------------------------------------------------
   Page Container
   ---------------------------------------------------------- */
.page {
    max-width: 960px;
    margin: 0 auto;
    padding: 1.5rem 1rem 4rem;
}

.page--wide {
    max-width: 1200px;
}

/* ----------------------------------------------------------
   Login Page
   ---------------------------------------------------------- */
.login-page {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 2rem 1rem;
    background: linear-gradient(160deg, #FFF8F0 0%, #fff3e6 100%);
}

.login-logo {
    font-size: 3.5rem;
    margin-bottom: .5rem;
    animation: gentle-bounce 2s ease-in-out infinite;
}

.login-title {
    font-size: 2rem;
    font-weight: 900;
    color: var(--color-primary);
    text-align: center;
    margin-bottom: .25rem;
}

.login-subtitle {
    font-size: 1rem;
    color: var(--color-text-muted);
    text-align: center;
    margin-bottom: 2.5rem;
}

/* ----------------------------------------------------------
   Leaderboard (login page)
   ---------------------------------------------------------- */
.leaderboard {
    background: var(--color-white);
    border-radius: var(--radius-lg);
    padding: 1.25rem 1.5rem;
    box-shadow: var(--shadow-md);
    width: 100%;
    max-width: 480px;
    margin-bottom: 2rem;
}

.leaderboard__title {
    font-size: 1.1rem;
    font-weight: 900;
    color: var(--color-text);
    text-align: center;
    margin-bottom: 1rem;
}

.leaderboard__table {
    width: 100%;
    border-collapse: collapse;
    font-size: .9rem;
}

.leaderboard__table th {
    font-size: .72rem;
    font-weight: 800;
    text-transform: uppercase;
    letter-spacing: .05em;
    color: var(--color-text-muted);
    padding: .3rem .5rem;
    text-align: left;
    border-bottom: 2px solid #f0f0f0;
}

.leaderboard__table td {
    padding: .6rem .5rem;
    border-bottom: 1px solid #f9f9f9;
    font-weight: 700;
    vertical-align: middle;
}

.leaderboard__table tr:last-child td {
    border-bottom: none;
}

.leaderboard__row--top td {
    background: linear-gradient(90deg, #fffbf0, transparent);
}

.leaderboard__pos {
    font-size: 1.1rem;
    text-align: center;
    width: 2rem;
}

.leaderboard__player {
    display: flex;
    align-items: center;
    gap: .4rem;
    font-weight: 800;
}

.leaderboard__stars {
    color: #e67e22;
    font-weight: 900;
}

.leaderboard__streak {
    color: #e17055;
    font-weight: 700;
}

.leaderboard__level {
    color: var(--color-text-muted);
    font-size: .82rem;
}

/* User selection cards */
.user-selection {
    display: flex;
    gap: 1.25rem;
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: 2rem;
}

.user-card {
    background: var(--color-white);
    border-radius: var(--radius-lg);
    padding: 1.5rem 2rem;
    box-shadow: var(--shadow-md);
    cursor: pointer;
    border: 3px solid transparent;
    transition: border-color var(--transition), transform var(--transition), box-shadow var(--transition);
    text-align: center;
    min-width: 140px;
    touch-action: manipulation;
}

.user-card:hover,
.user-card.selected {
    border-color: var(--color-primary);
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.user-card__avatar {
    font-size: 3rem;
    margin-bottom: .5rem;
    display: block;
}

.user-card__name {
    font-weight: 800;
    font-size: 1.1rem;
    color: var(--color-text);
}

/* PIN pad */
.pin-section {
    background: var(--color-white);
    border-radius: var(--radius-lg);
    padding: 1.75rem;
    box-shadow: var(--shadow-md);
    width: 100%;
    max-width: 340px;
    display: none; /* shown via JS */
}

.pin-section.visible {
    display: block;
}

.pin-label {
    text-align: center;
    font-weight: 700;
    font-size: 1rem;
    margin-bottom: 1rem;
    color: var(--color-text-muted);
}

/* PIN dots display */
.pin-display {
    display: flex;
    gap: .75rem;
    justify-content: center;
    margin-bottom: 1.25rem;
}

.pin-dot {
    width: 18px;
    height: 18px;
    border-radius: 50%;
    border: 3px solid #dfe6e9;
    background: transparent;
    transition: background var(--transition), border-color var(--transition);
}

.pin-dot.filled {
    background: var(--color-primary);
    border-color: var(--color-primary);
}

/* PIN numpad */
.pin-pad {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: .6rem;
    margin-bottom: 1rem;
}

.pin-key {
    aspect-ratio: 1;
    border-radius: var(--radius-md);
    background: var(--color-bg);
    font-size: 1.4rem;
    font-weight: 800;
    color: var(--color-text);
    border: 2px solid #dfe6e9;
    transition: background var(--transition), transform var(--transition);
    min-height: 60px;
    touch-action: manipulation;
}

.pin-key:hover, .pin-key:focus {
    background: var(--color-primary);
    color: var(--color-white);
    border-color: var(--color-primary);
}

.pin-key:active {
    transform: scale(.92);
}

.pin-key--delete {
    background: #ffeaa7;
    border-color: #fdcb6e;
}

.pin-key--zero {
    grid-column: 2; /* center the 0 */
}

/* Admin password field */
.admin-login-form {
    display: none;
    flex-direction: column;
    gap: .75rem;
    margin-top: 1rem;
}

.admin-login-form.visible {
    display: flex;
}

.admin-login-form input[type="password"] {
    padding: .75rem 1rem;
    border-radius: var(--radius-md);
    border: 2px solid #dfe6e9;
    font-family: var(--font-main);
    font-size: 1rem;
    width: 100%;
    transition: border-color var(--transition);
}

.admin-login-form input[type="password"]:focus {
    outline: none;
    border-color: var(--color-secondary);
}

/* Login feedback message */
.login-message {
    text-align: center;
    font-weight: 700;
    font-size: 1rem;
    padding: .75rem 1.25rem;
    border-radius: var(--radius-md);
    margin-top: 1rem;
    display: none;
}

.login-message.visible {
    display: block;
}

.login-message--error {
    background: #fff0f0;
    color: #c0392b;
}

.login-message--success {
    background: #f0fff8;
    color: #27ae60;
}

/* ----------------------------------------------------------
   Dashboard
   ---------------------------------------------------------- */
.dashboard-greeting {
    padding: 1.5rem 0 1rem;
    text-align: center;
}

.dashboard-greeting h1 {
    font-size: 1.75rem;
    font-weight: 900;
    color: var(--color-text);
    margin-bottom: .25rem;
}

.dashboard-greeting p {
    color: var(--color-text-muted);
    font-size: 1rem;
}

/* Zone grid */
.zone-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
    gap: 1.25rem;
    margin-top: 1.5rem;
}

.zone-card {
    background: var(--color-white);
    border-radius: var(--radius-lg);
    padding: 1.75rem 1.5rem;
    box-shadow: var(--shadow-sm);
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    gap: .75rem;
    border: 3px solid transparent;
    transition: transform var(--transition), box-shadow var(--transition), border-color var(--transition);
    position: relative;
    overflow: hidden;
}

.zone-card--unlocked {
    cursor: pointer;
    border-color: transparent;
}

.zone-card--unlocked:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
    border-color: var(--color-primary);
}

.zone-card--locked {
    opacity: .6;
    cursor: not-allowed;
}

.zone-card--locked::after {
    content: '🔒';
    position: absolute;
    top: .75rem;
    right: .75rem;
    font-size: 1rem;
}

.zone-card__icon {
    font-size: 3rem;
    line-height: 1;
}

.zone-card__title {
    font-size: 1.15rem;
    font-weight: 800;
    color: var(--color-text);
}

.zone-card__desc {
    font-size: .875rem;
    color: var(--color-text-muted);
    font-weight: 600;
}

.zone-card__badge {
    font-size: .75rem;
    font-weight: 700;
    padding: .25rem .75rem;
    border-radius: var(--radius-full);
    background: var(--color-bg);
    color: var(--color-text-muted);
}

.zone-card--unlocked .zone-card__badge {
    background: linear-gradient(135deg, var(--color-primary), var(--color-accent));
    color: var(--color-white);
}

/* Session reminder toast */
.session-reminder {
    position: fixed;
    bottom: 1.5rem;
    left: 50%;
    transform: translateX(-50%) translateY(200%);
    background: var(--color-white);
    border-radius: var(--radius-lg);
    padding: 1.25rem 2rem;
    box-shadow: var(--shadow-lg);
    text-align: center;
    max-width: 380px;
    width: calc(100% - 2rem);
    transition: transform .4s cubic-bezier(.34,1.56,.64,1);
    z-index: 999;
    border-top: 4px solid var(--color-success);
}

.session-reminder.visible {
    transform: translateX(-50%) translateY(0);
}

.session-reminder p {
    font-size: 1rem;
    font-weight: 700;
    color: var(--color-text);
    margin-bottom: .75rem;
}

/* ----------------------------------------------------------
   Memory Game Page
   ---------------------------------------------------------- */
.game-page {
    max-width: 800px;
    margin: 0 auto;
    padding: 1rem;
}

/* Difficulty selector */
.difficulty-screen {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 2rem 1rem;
    gap: 1.5rem;
}

.difficulty-screen h2 {
    font-size: 1.75rem;
    font-weight: 900;
    text-align: center;
    color: var(--color-text);
}

.difficulty-screen p {
    color: var(--color-text-muted);
    text-align: center;
    font-size: 1rem;
    max-width: 400px;
}

.difficulty-cards {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    justify-content: center;
    width: 100%;
}

.difficulty-card {
    background: var(--color-white);
    border-radius: var(--radius-lg);
    padding: 1.75rem 1.5rem;
    box-shadow: var(--shadow-md);
    cursor: pointer;
    border: 3px solid transparent;
    text-align: center;
    width: 200px;
    transition: transform var(--transition), border-color var(--transition), box-shadow var(--transition);
    touch-action: manipulation;
}

.difficulty-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.difficulty-card[data-diff="easy"]   { border-color: var(--color-success); }
.difficulty-card[data-diff="medium"] { border-color: var(--color-secondary); }
.difficulty-card[data-diff="hard"]   { border-color: var(--color-primary); }

.difficulty-card__emoji {
    font-size: 2.5rem;
    margin-bottom: .5rem;
}

.difficulty-card__title {
    font-size: 1.1rem;
    font-weight: 800;
    margin-bottom: .25rem;
}

.difficulty-card__info {
    font-size: .85rem;
    color: var(--color-text-muted);
    font-weight: 600;
}

/* Game HUD */
.game-hud {
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: var(--color-white);
    border-radius: var(--radius-md);
    padding: .75rem 1.25rem;
    box-shadow: var(--shadow-sm);
    margin-bottom: 1.25rem;
    flex-wrap: wrap;
    gap: .5rem;
}

.hud-stat {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: .1rem;
}

.hud-stat__label {
    font-size: .72rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: .05em;
    color: var(--color-text-muted);
}

.hud-stat__value {
    font-size: 1.25rem;
    font-weight: 900;
    color: var(--color-text);
}

/* Memory card grid */
.card-grid {
    display: grid;
    gap: .75rem;
    justify-content: center;
    margin: 0 auto;
}

/* Grid columns set by JS via inline style or class */
.card-grid--easy   { grid-template-columns: repeat(4, 1fr); }
.card-grid--medium { grid-template-columns: repeat(4, 1fr); }
.card-grid--hard   { grid-template-columns: repeat(5, 1fr); }

/* Memory card */
.memory-card {
    aspect-ratio: 1;
    position: relative;
    cursor: pointer;
    touch-action: manipulation;
    min-width: 60px;
    perspective: 600px;
}

.memory-card__inner {
    position: relative;
    width: 100%;
    height: 100%;
    transform-style: preserve-3d;
    transition: transform .45s ease;
    border-radius: var(--radius-md);
}

.memory-card.flipped .memory-card__inner {
    transform: rotateY(180deg);
}

.memory-card.matched .memory-card__inner {
    transform: rotateY(180deg);
}

.memory-card__front,
.memory-card__back {
    position: absolute;
    inset: 0;
    backface-visibility: hidden;
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: clamp(1.5rem, 4vw, 2.25rem);
    box-shadow: var(--shadow-sm);
}

/* Card front = face-down side (question mark) */
.memory-card__front {
    background: linear-gradient(135deg, var(--color-secondary), var(--color-secondary-dark));
    color: var(--color-white);
    font-size: clamp(1.25rem, 3vw, 1.75rem);
}

/* Card back = emoji side */
.memory-card__back {
    background: var(--color-white);
    transform: rotateY(180deg);
    border: 3px solid #f0f0f0;
}

/* Matched card glow */
.memory-card.matched .memory-card__back {
    background: linear-gradient(135deg, #f0fff8, #d4f8ed);
    border-color: var(--color-success);
    animation: matched-pulse 1s ease forwards;
}

/* Encouraging message popup */
.encourage-msg {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%) scale(0);
    background: var(--color-white);
    border-radius: var(--radius-lg);
    padding: 1rem 2rem;
    font-size: 1.25rem;
    font-weight: 900;
    color: var(--color-primary);
    box-shadow: var(--shadow-lg);
    z-index: 200;
    pointer-events: none;
    transition: transform .2s cubic-bezier(.34,1.56,.64,1), opacity .2s;
    opacity: 0;
}

.encourage-msg.visible {
    transform: translate(-50%, -50%) scale(1);
    opacity: 1;
}

/* Floating star reward */
.float-star {
    position: fixed;
    font-size: 1.25rem;
    font-weight: 900;
    color: #f39c12;
    pointer-events: none;
    z-index: 300;
    animation: float-up .9s ease forwards;
}

/* Preview inline banner — sits above the cards, never blocks them */
.preview-inline-banner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    background: linear-gradient(135deg, var(--color-secondary), var(--color-secondary-dark));
    color: var(--color-white);
    border-radius: var(--radius-md);
    padding: .75rem 1.25rem;
    margin-bottom: .75rem;
    font-weight: 800;
    font-size: 1rem;
    box-shadow: var(--shadow-sm);
    animation: spin-in .3s ease;
}

.preview-timer {
    background: rgba(255,255,255,.25);
    border-radius: var(--radius-full);
    padding: .3rem .9rem;
    font-size: 1.1rem;
    font-weight: 900;
    min-width: 3rem;
    text-align: center;
}

/* ----------------------------------------------------------
   Celebration / End-of-game Screen
   ---------------------------------------------------------- */
.celebration-screen {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,.55);
    z-index: 500;
    align-items: center;
    justify-content: center;
    padding: 1rem;
}

.celebration-screen.visible {
    display: flex;
}

.celebration-card {
    background: var(--color-white);
    border-radius: var(--radius-xl);
    padding: 2.5rem 2rem;
    max-width: 420px;
    width: 100%;
    text-align: center;
    box-shadow: var(--shadow-lg);
    position: relative;
    overflow: hidden;
}

.celebration-title {
    font-size: 2rem;
    font-weight: 900;
    color: var(--color-primary);
    margin-bottom: .5rem;
}

.celebration-subtitle {
    font-size: 1rem;
    color: var(--color-text-muted);
    margin-bottom: 1.5rem;
}

.celebration-stats {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1rem;
    margin-bottom: 1.5rem;
}

.cel-stat {
    background: var(--color-bg);
    border-radius: var(--radius-md);
    padding: 1rem;
}

.cel-stat__label {
    font-size: .8rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: .05em;
    color: var(--color-text-muted);
    margin-bottom: .25rem;
}

.cel-stat__value {
    font-size: 1.5rem;
    font-weight: 900;
    color: var(--color-text);
}

.stars-earned {
    font-size: 2rem;
    font-weight: 900;
    color: #f39c12;
    margin-bottom: 1rem;
    display: block;
}

.next-difficulty-hint {
    font-size: .9rem;
    font-weight: 700;
    color: var(--color-secondary-dark);
    background: #f0fffe;
    border-radius: var(--radius-md);
    padding: .75rem 1rem;
    margin-bottom: 1.25rem;
}

.celebration-actions {
    display: flex;
    flex-direction: column;
    gap: .6rem;
}

/* Confetti particles (CSS only) */
.confetti-container {
    position: absolute;
    inset: 0;
    pointer-events: none;
    overflow: hidden;
}

.confetti-piece {
    position: absolute;
    top: -10px;
    width: 10px;
    height: 10px;
    border-radius: 2px;
    animation: confetti-fall linear forwards;
}

/* ----------------------------------------------------------
   Admin Panel
   ---------------------------------------------------------- */
.admin-page {
    background: #f5f6fa;
    min-height: 100vh;
}

.admin-topbar {
    background: #2D3436;
    color: var(--color-white);
    padding: 1rem 1.5rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    position: sticky;
    top: 0;
    z-index: 100;
}

.admin-topbar h1 {
    font-size: 1.15rem;
    font-weight: 800;
}

.admin-topbar .btn-logout {
    background: #e17055;
    color: var(--color-white);
    padding: .4rem 1rem;
    border-radius: var(--radius-full);
    font-size: .9rem;
    font-weight: 700;
}

.admin-container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 2rem 1rem 4rem;
}

.admin-section {
    margin-bottom: 2rem;
}

.admin-section h2 {
    font-size: 1.15rem;
    font-weight: 800;
    color: var(--color-text);
    margin-bottom: 1rem;
    padding-bottom: .5rem;
    border-bottom: 2px solid #dfe6e9;
}

/* Stats overview cards */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
    gap: 1rem;
}

.stat-card {
    background: var(--color-white);
    border-radius: var(--radius-md);
    padding: 1.25rem;
    box-shadow: var(--shadow-sm);
    border-left: 4px solid var(--color-primary);
}

.stat-card:nth-child(2) { border-left-color: var(--color-secondary); }
.stat-card:nth-child(3) { border-left-color: var(--color-accent); }
.stat-card:nth-child(4) { border-left-color: var(--color-success); }
.stat-card:nth-child(5) { border-left-color: #a29bfe; }

.stat-card__label {
    font-size: .8rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: .05em;
    color: var(--color-text-muted);
    margin-bottom: .4rem;
}

.stat-card__value {
    font-size: 1.75rem;
    font-weight: 900;
    color: var(--color-text);
}

/* Activity chart */
.chart-wrap {
    background: var(--color-white);
    border-radius: var(--radius-md);
    padding: 1.5rem;
    box-shadow: var(--shadow-sm);
    overflow-x: auto;
}

.bar-chart {
    display: flex;
    align-items: flex-end;
    gap: .5rem;
    height: 160px;
    min-width: 400px;
}

.bar-chart__bar-wrap {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: .3rem;
    height: 100%;
    justify-content: flex-end;
}

.bar-chart__bar {
    width: 100%;
    background: linear-gradient(180deg, var(--color-primary), #ff9999);
    border-radius: 4px 4px 0 0;
    min-height: 4px;
    transition: height .3s ease;
}

.bar-chart__label {
    font-size: .7rem;
    font-weight: 700;
    color: var(--color-text-muted);
    text-align: center;
}

.bar-chart__count {
    font-size: .75rem;
    font-weight: 800;
    color: var(--color-primary);
}

/* Session history table */
.history-table {
    width: 100%;
    border-collapse: collapse;
    font-size: .9rem;
}

.history-table th,
.history-table td {
    padding: .75rem 1rem;
    text-align: left;
    border-bottom: 1px solid #f0f0f0;
}

.history-table th {
    font-weight: 800;
    font-size: .8rem;
    text-transform: uppercase;
    letter-spacing: .05em;
    color: var(--color-text-muted);
    background: var(--color-bg);
}

.history-table tr:hover td {
    background: #fafafa;
}

.diff-badge {
    display: inline-block;
    padding: .2rem .65rem;
    border-radius: var(--radius-full);
    font-size: .78rem;
    font-weight: 700;
}

.diff-badge--easy   { background: #d4f8ed; color: #27ae60; }
.diff-badge--medium { background: #e0f9f8; color: #00b894; }
.diff-badge--hard   { background: #ffeaa7; color: #e17055; }

.table-wrap {
    background: var(--color-white);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-sm);
    overflow-x: auto;
}

/* ----------------------------------------------------------
   Animations / Keyframes
   ---------------------------------------------------------- */
@keyframes gentle-bounce {
    0%, 100% { transform: translateY(0); }
    50%       { transform: translateY(-10px); }
}

@keyframes matched-pulse {
    0%   { box-shadow: 0 0 0 0 rgba(52,211,153,.6); }
    50%  { box-shadow: 0 0 0 12px rgba(52,211,153,0); }
    100% { box-shadow: 0 0 0 0 rgba(52,211,153,0); }
}

@keyframes float-up {
    0%   { transform: translateY(0) scale(1); opacity: 1; }
    100% { transform: translateY(-80px) scale(1.3); opacity: 0; }
}

@keyframes confetti-fall {
    0%   { transform: translateY(-10px) rotate(0deg); opacity: 1; }
    100% { transform: translateY(110vh) rotate(720deg); opacity: .5; }
}

@keyframes spin-in {
    0%   { transform: scale(0) rotate(-30deg); opacity: 0; }
    100% { transform: scale(1) rotate(0deg);   opacity: 1; }
}

/* ----------------------------------------------------------
   Responsive — Tablet (≥600px)
   ---------------------------------------------------------- */
@media (min-width: 600px) {
    .topbar {
        padding: .75rem 2rem;
    }

    .celebration-actions {
        flex-direction: row;
        justify-content: center;
    }

    .stats-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

/* ----------------------------------------------------------
   Responsive — Desktop (≥960px)
   ---------------------------------------------------------- */
@media (min-width: 960px) {
    .zone-grid {
        grid-template-columns: repeat(3, 1fr);
    }

    .stats-grid {
        grid-template-columns: repeat(5, 1fr);
    }

    .card-grid--easy   { gap: 1rem; }
    .card-grid--medium { gap: 1rem; }
    .card-grid--hard   { gap: .85rem; }
}

/* ----------------------------------------------------------
   VS Mode — Turn-based Multiplayer
   ---------------------------------------------------------- */

/* Scoreboard strip */
.vs-scoreboard {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    background: var(--color-white);
    border-radius: var(--radius-md);
    padding: .75rem 1rem;
    box-shadow: var(--shadow-sm);
    margin-bottom: 1rem;
}

/* Player score cards */
.vs-player-card {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: .2rem;
    padding: .6rem 1.25rem;
    border-radius: var(--radius-md);
    border: 3px solid #f0f0f0;
    transition: border-color var(--transition), background var(--transition),
                box-shadow var(--transition);
    flex: 1;
    max-width: 140px;
    cursor: default;
}

.vs-player-card--active.vs-player-card--p0 {
    border-color: var(--color-primary);
    background: #fff5f5;
    box-shadow: 0 0 0 3px rgba(255,107,107,.15);
}

.vs-player-card--active.vs-player-card--p1 {
    border-color: var(--color-secondary);
    background: #f0fffe;
    box-shadow: 0 0 0 3px rgba(78,205,196,.15);
}

.vs-player-card__avatar { font-size: 1.75rem; line-height: 1; }

.vs-player-card__name {
    font-size: .82rem;
    font-weight: 800;
    color: var(--color-text-muted);
    text-align: center;
}

.vs-player-card__score {
    font-size: 2rem;
    font-weight: 900;
    line-height: 1;
}

.vs-player-card--p0 .vs-player-card__score { color: var(--color-primary); }
.vs-player-card--p1 .vs-player-card__score { color: var(--color-secondary); }

.vs-separator {
    font-size: 1.25rem;
    font-weight: 900;
    color: var(--color-text-muted);
    flex-shrink: 0;
}

/* Turn indicator bar */
.vs-turn-indicator {
    border-radius: var(--radius-md);
    padding: .65rem 1.25rem;
    font-size: .95rem;
    font-weight: 800;
    color: var(--color-white);
    text-align: center;
    margin-bottom: 1rem;
    transition: background .4s ease;
    background: linear-gradient(135deg, var(--color-primary), #ff8e8e);
}

/* Turn-change overlay — full screen */
.vs-turn-overlay {
    display: none;
    position: fixed;
    inset: 0;
    z-index: 700;
    align-items: center;
    justify-content: center;
    flex-direction: column;
    gap: 1.5rem;
    text-align: center;
    padding: 2rem;
    animation: spin-in .25s ease;
}

.vs-turn-overlay.visible {
    display: flex;
}

.vs-turn-overlay__name {
    font-size: clamp(1.75rem, 6vw, 2.75rem);
    font-weight: 900;
    color: var(--color-white);
    text-shadow: 0 2px 8px rgba(0,0,0,.25);
}

.vs-turn-overlay__subtitle {
    font-size: 1.15rem;
    font-weight: 700;
    color: rgba(255,255,255,.9);
}

.vs-turn-overlay__btn {
    background: rgba(255,255,255,.25);
    color: var(--color-white);
    border: 3px solid rgba(255,255,255,.7);
    border-radius: var(--radius-full);
    padding: .85rem 2.5rem;
    font-family: var(--font-main);
    font-size: 1.1rem;
    font-weight: 900;
    cursor: pointer;
    transition: background .2s, transform .15s;
    touch-action: manipulation;
}

.vs-turn-overlay__btn:hover,
.vs-turn-overlay__btn:active {
    background: rgba(255,255,255,.4);
    transform: scale(1.04);
}

/* VS final scores (celebration screen) */
.vs-final-scores {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 1.5rem;
}

.vs-final-player {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: .35rem;
    padding: 1.25rem 1rem;
    border-radius: var(--radius-lg);
    border: 3px solid #f0f0f0;
    flex: 1;
    background: var(--color-bg);
}

.vs-final-player--winner {
    background: linear-gradient(135deg, #fffbe8, #fff9e6);
    border-color: #f39c12;
    box-shadow: 0 0 0 3px rgba(243,156,18,.2);
    position: relative;
}

.vs-final-player--winner::before {
    content: '🏆';
    position: absolute;
    top: -.9rem;
    left: 50%;
    transform: translateX(-50%);
    font-size: 1.5rem;
}

.vs-divider {
    font-size: 1.1rem;
    font-weight: 900;
    color: var(--color-text-muted);
    flex-shrink: 0;
}

/* ----------------------------------------------------------
   Daily Challenge Card
   ---------------------------------------------------------- */
.daily-challenge-card {
    display: flex;
    align-items: center;
    gap: 1rem;
    background: var(--color-white);
    border-radius: var(--radius-md);
    padding: 1rem 1.25rem;
    box-shadow: var(--shadow-sm);
    border-left: 4px solid var(--color-secondary);
    margin-bottom: .75rem;
    transition: border-color var(--transition);
}

.daily-challenge-card--done {
    border-left-color: var(--color-success);
    background: linear-gradient(135deg, #f0fff8, #e8fff5);
}

.daily-challenge-icon {
    font-size: 2rem;
    flex-shrink: 0;
    line-height: 1;
}

.daily-challenge-body {
    flex: 1;
    min-width: 0;
}

.daily-challenge-title {
    font-size: 1rem;
    font-weight: 800;
    color: var(--color-text);
    margin-bottom: .15rem;
}

.daily-challenge-desc {
    font-size: .82rem;
    color: var(--color-text-muted);
    font-weight: 600;
}

.daily-challenge-bonus {
    font-size: 1.05rem;
    font-weight: 900;
    color: #f39c12;
    flex-shrink: 0;
    text-align: right;
}

/* ----------------------------------------------------------
   Dashboard generic section
   ---------------------------------------------------------- */
.dash-section {
    margin-top: 1.5rem;
}

.dash-section__title {
    font-size: 1.05rem;
    font-weight: 800;
    color: var(--color-text);
    margin-bottom: .85rem;
    display: flex;
    align-items: center;
    gap: .6rem;
}

.badges-count {
    font-size: .8rem;
    font-weight: 700;
    color: var(--color-text-muted);
    background: var(--color-bg);
    padding: .2rem .65rem;
    border-radius: var(--radius-full);
}

/* ----------------------------------------------------------
   Personal records
   ---------------------------------------------------------- */
.records-grid {
    display: flex;
    gap: .75rem;
    flex-wrap: wrap;
}

.record-card {
    background: var(--color-white);
    border-radius: var(--radius-md);
    padding: .85rem 1.1rem;
    box-shadow: var(--shadow-sm);
    flex: 1;
    min-width: 130px;
}

.record-card__diff {
    font-size: .78rem;
    font-weight: 800;
    text-transform: uppercase;
    letter-spacing: .04em;
    color: var(--color-text-muted);
    margin-bottom: .4rem;
}

.record-card__stats {
    display: flex;
    flex-direction: column;
    gap: .2rem;
    font-size: .92rem;
    font-weight: 700;
    color: var(--color-text);
}

/* ----------------------------------------------------------
   Badges wall
   ---------------------------------------------------------- */
.badges-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(74px, 1fr));
    gap: .75rem;
}

.badge-item {
    background: var(--color-white);
    border-radius: var(--radius-md);
    padding: .85rem .5rem .65rem;
    box-shadow: var(--shadow-sm);
    text-align: center;
    transition: transform var(--transition), box-shadow var(--transition);
    cursor: default;
    position: relative;
}

.badge-item--earned {
    background: linear-gradient(145deg, #fff9f0, #fff);
    border: 2px solid #FFE66D;
}

.badge-item--locked {
    opacity: .5;
    filter: grayscale(1);
}

.badge-item--locked .badge-item__icon {
    font-size: 1.2rem;
}

.badge-item--earned:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-md);
    opacity: 1;
}

.badge-item--locked:hover {
    opacity: .75;
    filter: grayscale(.5);
}

.badge-item__icon {
    font-size: 1.75rem;
    line-height: 1;
    margin-bottom: .3rem;
}

.badge-item__name {
    font-size: .62rem;
    font-weight: 700;
    color: var(--color-text-muted);
    line-height: 1.2;
}

.badge-item--earned .badge-item__name {
    color: var(--color-text);
    font-weight: 800;
}

/* ----------------------------------------------------------
   Shop modal
   ---------------------------------------------------------- */
.shop-overlay {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,.55);
    z-index: 800;
    align-items: center;
    justify-content: center;
    padding: 1rem;
}

.shop-overlay.visible {
    display: flex;
}

.shop-modal {
    background: var(--color-white);
    border-radius: var(--radius-xl);
    padding: 1.75rem 1.5rem;
    max-width: 480px;
    width: 100%;
    max-height: 90vh;
    overflow-y: auto;
    box-shadow: var(--shadow-lg);
}

.shop-modal__header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: .5rem;
}

.shop-modal__header h2 {
    font-size: 1.25rem;
    font-weight: 900;
}

.shop-modal__close {
    background: #f0f0f0;
    border: none;
    border-radius: 50%;
    width: 32px;
    height: 32px;
    font-size: 1rem;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background var(--transition);
}

.shop-modal__close:hover { background: #e0e0e0; }

.shop-modal__stars {
    font-size: .9rem;
    color: var(--color-text-muted);
    font-weight: 600;
    margin-bottom: 1.25rem;
}

.shop-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(80px, 1fr));
    gap: .75rem;
    margin-bottom: 1rem;
}

.shop-item {
    background: var(--color-bg);
    border-radius: var(--radius-md);
    padding: .85rem .5rem .65rem;
    text-align: center;
    border: 3px solid transparent;
    cursor: pointer;
    transition: transform var(--transition), border-color var(--transition), box-shadow var(--transition);
}

.shop-item:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-sm);
}

.shop-item--active {
    border-color: var(--color-success);
    background: #f0fff8;
    cursor: default;
}

.shop-item--owned {
    border-color: var(--color-secondary);
    background: #f0fffe;
}

.shop-item--locked {
    opacity: .5;
    cursor: not-allowed;
}

.shop-item__emoji {
    font-size: 2rem;
    line-height: 1;
    margin-bottom: .3rem;
}

.shop-item__name {
    font-size: .7rem;
    font-weight: 800;
    color: var(--color-text);
    margin-bottom: .2rem;
}

.shop-item__cost {
    font-size: .72rem;
    font-weight: 700;
    color: var(--color-text-muted);
}

/* ----------------------------------------------------------
   Milestone overlay (full-screen star celebration)
   ---------------------------------------------------------- */
.milestone-overlay {
    display: none;
    position: fixed;
    inset: 0;
    z-index: 900;
    background: linear-gradient(160deg, #2d3436, #1a1a2e);
    align-items: center;
    justify-content: center;
    flex-direction: column;
    gap: 1rem;
    text-align: center;
    padding: 2rem;
}

.milestone-overlay.visible {
    display: flex;
}

.milestone-number {
    font-size: clamp(4rem, 15vw, 8rem);
    font-weight: 900;
    color: #FFE66D;
    text-shadow: 0 0 40px rgba(255,230,109,.6), 0 4px 20px rgba(0,0,0,.5);
    line-height: 1;
    animation: milestone-pop .5s cubic-bezier(.34,1.56,.64,1) both;
}

.milestone-label {
    font-size: clamp(1.25rem, 5vw, 2rem);
    font-weight: 900;
    color: var(--color-white);
    letter-spacing: .05em;
    text-transform: uppercase;
}

.milestone-sub {
    font-size: 1.1rem;
    font-weight: 700;
    color: rgba(255,255,255,.8);
}

.milestone-btn {
    background: var(--color-accent);
    color: var(--color-text);
    border: none;
    border-radius: var(--radius-full);
    padding: .9rem 2.5rem;
    font-family: var(--font-main);
    font-size: 1.1rem;
    font-weight: 900;
    cursor: pointer;
    margin-top: .5rem;
    transition: transform .15s, filter .15s;
    touch-action: manipulation;
}

.milestone-btn:hover, .milestone-btn:active {
    filter: brightness(.95);
    transform: scale(1.04);
}

/* New badge row inside celebration */
.new-badges-row {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: .4rem;
    background: #fff9e6;
    border-radius: var(--radius-md);
    padding: .75rem 1rem;
    margin-bottom: .75rem;
    font-size: .82rem;
}

.new-badges-row .badge-icons {
    display: flex;
    gap: .5rem;
    font-size: 1.5rem;
    flex-wrap: wrap;
    justify-content: center;
}

@keyframes milestone-pop {
    0%   { transform: scale(0) rotate(-10deg); opacity: 0; }
    100% { transform: scale(1) rotate(0deg);   opacity: 1; }
}