/* ========================================
   Material Design System - Dark Theme
======================================== */
:root {
    /* Material Design Colors - Dark Theme */
    --md-primary: #90CAF9;
    --md-primary-variant: #42A5F5;
    --md-secondary: #F48FB1;
    --md-secondary-variant: #EC407A;

    --md-background: #121212;
    --md-surface: #1E1E1E;
    --md-surface-variant: #2D2D2D;
    --md-error: #CF6679;

    --md-on-primary: #000000;
    --md-on-secondary: #000000;
    --md-on-background: #E1E1E1;
    --md-on-surface: #E1E1E1;
    --md-on-surface-medium: rgba(255, 255, 255, 0.6);
    --md-on-surface-disabled: rgba(255, 255, 255, 0.38);

    /* Dynamic theme colors */
    --theme-primary: var(--md-primary);
    --theme-primary-variant: var(--md-primary-variant);

    /* Typography */
    --font-family: 'Noto Sans KR', Roboto, -apple-system, BlinkMacSystemFont, sans-serif;

    /* Spacing (Material 8dp grid) */
    --spacing-1: 4px;
    --spacing-2: 8px;
    --spacing-3: 12px;
    --spacing-4: 16px;
    --spacing-5: 20px;
    --spacing-6: 24px;
    --spacing-8: 32px;
    --spacing-10: 40px;
    --spacing-12: 48px;

    /* Border Radius */
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-xl: 16px;
    --radius-full: 9999px;

    /* Transitions */
    --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-standard: 300ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-emphasized: 500ms cubic-bezier(0.4, 0, 0.2, 1);

    /* Shadows */
    --shadow-1: 0 1px 3px rgba(0, 0, 0, 0.12), 0 1px 2px rgba(0, 0, 0, 0.24);
    --shadow-2: 0 3px 6px rgba(0, 0, 0, 0.16), 0 3px 6px rgba(0, 0, 0, 0.23);
    --shadow-4: 0 10px 20px rgba(0, 0, 0, 0.19), 0 6px 6px rgba(0, 0, 0, 0.23);
    --shadow-8: 0 14px 28px rgba(0, 0, 0, 0.25), 0 10px 10px rgba(0, 0, 0, 0.22);
}

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

html {
    font-size: 16px;
}

body {
    font-family: var(--font-family);
    background: var(--md-background);
    color: var(--md-on-background);
    min-height: 100vh;
    line-height: 1.5;
}

/* App Container */
.app-container {
    min-height: 100vh;
    background: var(--md-background);
}

/* Screens */
.screen {
    position: fixed;
    inset: 0;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transform: translateY(20px);
    transition: all var(--transition-emphasized);
    padding: var(--spacing-6);
    overflow-y: auto;
}

.screen.active {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

/* Background Shapes */
.floating-shapes {
    position: absolute;
    inset: 0;
    pointer-events: none;
    z-index: 0;
    overflow: hidden;
}

.shape {
    position: absolute;
    border-radius: 50%;
    opacity: 0.03;
    background: var(--theme-primary);
}

.shape-1 {
    width: 400px;
    height: 400px;
    top: -150px;
    left: -150px;
}

.shape-2 {
    width: 300px;
    height: 300px;
    top: 40%;
    right: -100px;
}

.shape-3 {
    width: 200px;
    height: 200px;
    bottom: 5%;
    left: 5%;
}

.shape-4 {
    width: 350px;
    height: 350px;
    bottom: -150px;
    right: 15%;
}

/* Start Screen */
#start-screen .content {
    position: relative;
    z-index: 1;
    text-align: center;
    max-width: 560px;
    width: 100%;
}

/* Logo */
.logo {
    margin-bottom: var(--spacing-12);
}

.logo-icon {
    font-size: 56px;
    display: block;
    margin-bottom: var(--spacing-4);
}

.logo h1 {
    font-size: 28px;
    font-weight: 500;
    color: var(--md-on-background);
    margin-bottom: var(--spacing-2);
    letter-spacing: 0.02em;
}

.logo h1 .highlight {
    color: var(--md-secondary);
    font-weight: 700;
}

.subtitle {
    font-size: 14px;
    color: var(--md-on-surface-medium);
}

/* Sections */
.gender-selection,
.round-selection,
.custom-names-section {
    margin-bottom: var(--spacing-8);
}

.gender-selection h2,
.round-selection h2,
.custom-names-section h2 {
    font-size: 14px;
    font-weight: 500;
    margin-bottom: var(--spacing-4);
    color: var(--md-on-surface-medium);
    text-transform: uppercase;
    letter-spacing: 0.08em;
}

.custom-names-section h2 {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-2);
}

.optional-badge {
    font-size: 11px;
    background: var(--md-surface-variant);
    padding: 2px 8px;
    border-radius: var(--radius-full);
    color: var(--md-on-surface-disabled);
    font-weight: 400;
    text-transform: none;
    letter-spacing: 0;
}

/* Gender Buttons */
.gender-buttons {
    display: flex;
    gap: var(--spacing-4);
    justify-content: center;
}

.gender-btn {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-2);
    padding: var(--spacing-6) var(--spacing-10);
    background: var(--md-surface);
    border: 2px solid transparent;
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: all var(--transition-standard);
}

.gender-btn:hover {
    background: var(--md-surface-variant);
    transform: translateY(-2px);
}

.gender-btn.selected {
    border-color: var(--theme-primary);
    background: rgba(144, 202, 249, 0.08);
}

.gender-btn[data-gender="boy"].selected {
    border-color: var(--md-primary);
    background: rgba(144, 202, 249, 0.08);
}

.gender-btn[data-gender="girl"].selected {
    border-color: var(--md-secondary);
    background: rgba(244, 143, 177, 0.08);
}

.gender-icon {
    font-size: 40px;
}

.gender-text {
    font-size: 14px;
    font-weight: 500;
    color: var(--md-on-surface);
}

/* Custom Names Input */
.name-input-form {
    margin-bottom: var(--spacing-4);
}

.input-group {
    display: flex;
    gap: var(--spacing-2);
    max-width: 480px;
    margin: 0 auto;
}

.input-group input {
    flex: 1;
    padding: var(--spacing-3) var(--spacing-4);
    background: var(--md-surface);
    border: 1px solid var(--md-surface-variant);
    border-radius: var(--radius-sm);
    color: var(--md-on-surface);
    font-size: 14px;
    font-family: var(--font-family);
    transition: all var(--transition-fast);
}

.input-group input:focus {
    outline: none;
    border-color: var(--theme-primary);
    background: var(--md-surface-variant);
}

.input-group input::placeholder {
    color: var(--md-on-surface-disabled);
}

.add-name-btn {
    padding: var(--spacing-3);
    background: var(--theme-primary);
    border: none;
    border-radius: var(--radius-sm);
    color: var(--md-on-primary);
    cursor: pointer;
    transition: all var(--transition-fast);
    display: flex;
    align-items: center;
    justify-content: center;
    min-width: 44px;
}

.add-name-btn:hover {
    opacity: 0.9;
    box-shadow: var(--shadow-2);
}

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

.add-name-btn svg {
    width: 20px;
    height: 20px;
}

/* Custom Names List */
.custom-names-list {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-2);
    justify-content: center;
    max-width: 560px;
    margin: 0 auto var(--spacing-3);
    max-height: 160px;
    overflow-y: auto;
    padding: var(--spacing-2);
}

.custom-names-list::-webkit-scrollbar {
    width: 4px;
}

.custom-names-list::-webkit-scrollbar-track {
    background: transparent;
}

.custom-names-list::-webkit-scrollbar-thumb {
    background: var(--md-surface-variant);
    border-radius: var(--radius-full);
}

.custom-name-tag {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-1);
    padding: var(--spacing-2) var(--spacing-3);
    background: var(--md-surface);
    border: 1px solid var(--theme-primary);
    border-radius: var(--radius-full);
    font-size: 13px;
    color: var(--md-on-surface);
    animation: chip-appear 200ms ease-out;
}

@keyframes chip-appear {
    from {
        opacity: 0;
        transform: scale(0.9);
    }

    to {
        opacity: 1;
        transform: scale(1);
    }
}

.custom-name-tag .tag-name {
    font-weight: 500;
    color: var(--theme-primary);
}

.custom-name-tag .tag-meaning {
    color: var(--md-on-surface-disabled);
    font-size: 12px;
}

.custom-name-tag .remove-btn {
    background: transparent;
    border: none;
    color: var(--md-on-surface-disabled);
    cursor: pointer;
    padding: 0;
    margin-left: var(--spacing-1);
    font-size: 16px;
    line-height: 1;
    transition: color var(--transition-fast);
    width: 18px;
    height: 18px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
}

.custom-name-tag .remove-btn:hover {
    color: var(--md-error);
    background: rgba(207, 102, 121, 0.1);
}

.custom-names-info {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-2);
    font-size: 12px;
    color: var(--md-on-surface-disabled);
}

.custom-names-info .info-icon {
    font-size: 14px;
}

.custom-names-info strong {
    color: var(--theme-primary);
    font-weight: 500;
}

/* Round Buttons */
.round-buttons {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-2);
    justify-content: center;
}

.round-btn {
    padding: var(--spacing-3) var(--spacing-6);
    background: var(--md-surface);
    border: 1px solid var(--md-surface-variant);
    border-radius: var(--radius-full);
    color: var(--md-on-surface);
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.round-btn:hover {
    background: var(--md-surface-variant);
}

.round-btn.selected {
    border-color: var(--theme-primary);
    background: var(--theme-primary);
    color: var(--md-on-primary);
}

/* Start Button */
.start-btn {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-2);
    padding: var(--spacing-4) var(--spacing-8);
    background: var(--theme-primary);
    border: none;
    border-radius: var(--radius-full);
    color: var(--md-on-primary);
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-standard);
    box-shadow: var(--shadow-2);
    text-transform: uppercase;
    letter-spacing: 0.08em;
}

.start-btn:hover {
    box-shadow: var(--shadow-4);
    transform: translateY(-1px);
}

.start-btn:active {
    transform: translateY(0);
}

.start-btn svg {
    width: 20px;
    height: 20px;
    transition: transform var(--transition-fast);
}

.start-btn:hover svg {
    transform: translateX(2px);
}

/* Game Screen */
#game-screen {
    padding: var(--spacing-6);
}

.game-header {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    padding: var(--spacing-4) var(--spacing-6);
}

.progress-info {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-2);
}

.round-badge {
    background: var(--theme-primary);
    color: var(--md-on-primary);
    padding: var(--spacing-1) var(--spacing-3);
    border-radius: var(--radius-full);
    font-size: 12px;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.04em;
}

.match-count {
    color: var(--md-on-surface-medium);
    font-size: 13px;
}

.progress-bar {
    width: 100%;
    height: 4px;
    background: var(--md-surface-variant);
    border-radius: var(--radius-full);
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    background: var(--theme-primary);
    border-radius: var(--radius-full);
    transition: width var(--transition-standard);
    width: 0%;
}

/* Battle Arena */
.battle-arena {
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-6);
    width: 100%;
    max-width: 800px;
}

.vs-indicator {
    position: absolute;
    z-index: 10;
    width: 48px;
    height: 48px;
    background: var(--md-surface);
    border: 2px solid var(--theme-primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 14px;
    font-weight: 700;
    color: var(--theme-primary);
    box-shadow: var(--shadow-4);
}

.name-cards {
    display: flex;
    gap: var(--spacing-6);
    width: 100%;
}

/* Name Card */
.name-card {
    flex: 1;
    position: relative;
    background: var(--md-surface);
    border: 2px solid transparent;
    border-radius: var(--radius-xl);
    padding: var(--spacing-10) var(--spacing-6);
    cursor: pointer;
    transition: all var(--transition-standard);
    min-height: 220px;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-2);
}

.name-card:hover {
    transform: translateY(-4px);
    border-color: var(--theme-primary);
    box-shadow: var(--shadow-4);
}

.card-glow {
    display: none;
}

.card-content {
    position: relative;
    z-index: 1;
    text-align: center;
}

.name-text {
    display: block;
    font-size: 36px;
    font-weight: 500;
    margin-bottom: var(--spacing-3);
    color: var(--theme-primary);
}

.name-meaning {
    display: block;
    font-size: 14px;
    color: var(--md-on-surface-medium);
}

/* Card Animation */
.name-card.selected {
    animation: card-select 400ms ease-out;
    border-color: var(--theme-primary);
    background: rgba(144, 202, 249, 0.08);
}

.name-card.eliminated {
    animation: card-fade 400ms ease-out forwards;
}

@keyframes card-select {
    0% {
        transform: scale(1);
    }

    50% {
        transform: scale(1.02);
    }

    100% {
        transform: scale(1);
    }
}

@keyframes card-fade {
    from {
        opacity: 1;
        transform: scale(1);
    }

    to {
        opacity: 0.3;
        transform: scale(0.98);
    }
}

.instruction {
    position: absolute;
    bottom: var(--spacing-6);
    color: var(--md-on-surface-disabled);
    font-size: 13px;
}

/* Result Screen */
#result-screen {
    background: var(--md-background);
}

.result-content {
    text-align: center;
    z-index: 1;
    animation: result-appear 500ms ease-out;
}

@keyframes result-appear {
    from {
        opacity: 0;
        transform: translateY(20px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.crown {
    font-size: 64px;
    margin-bottom: var(--spacing-4);
}

#result-screen h2 {
    font-size: 14px;
    color: var(--md-on-surface-medium);
    margin-bottom: var(--spacing-6);
    font-weight: 400;
    text-transform: uppercase;
    letter-spacing: 0.08em;
}

.winner-card {
    background: var(--theme-primary);
    padding: var(--spacing-10) var(--spacing-12);
    border-radius: var(--radius-xl);
    margin-bottom: var(--spacing-6);
    box-shadow: var(--shadow-8);
}

.winner-name {
    display: block;
    font-size: 48px;
    font-weight: 500;
    color: var(--md-on-primary);
    margin-bottom: var(--spacing-2);
}

.winner-meaning {
    display: block;
    font-size: 16px;
    color: rgba(0, 0, 0, 0.7);
}

.result-message {
    color: var(--md-on-surface-medium);
    margin-bottom: var(--spacing-8);
    font-size: 14px;
}

.result-actions {
    display: flex;
    gap: var(--spacing-3);
    justify-content: center;
    flex-wrap: wrap;
}

.action-btn {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-2);
    padding: var(--spacing-3) var(--spacing-6);
    border-radius: var(--radius-full);
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-fast);
    border: none;
    text-transform: uppercase;
    letter-spacing: 0.04em;
}

.action-btn.primary {
    background: var(--theme-primary);
    color: var(--md-on-primary);
    box-shadow: var(--shadow-2);
}

.action-btn.primary:hover {
    box-shadow: var(--shadow-4);
}

.action-btn.secondary {
    background: transparent;
    color: var(--theme-primary);
    border: 1px solid var(--theme-primary);
}

.action-btn.secondary:hover {
    background: rgba(144, 202, 249, 0.08);
}

/* Confetti */
.confetti {
    position: absolute;
    inset: 0;
    pointer-events: none;
    overflow: hidden;
}

.confetti-piece {
    position: absolute;
    width: 8px;
    height: 8px;
    animation: confetti-fall 3s linear forwards;
}

@keyframes confetti-fall {
    from {
        transform: translateY(-50px) rotate(0deg);
        opacity: 1;
    }

    to {
        transform: translateY(100vh) rotate(720deg);
        opacity: 0;
    }
}

/* Responsive */
@media (max-width: 768px) {
    .logo h1 {
        font-size: 24px;
    }

    .gender-buttons {
        flex-direction: column;
        gap: var(--spacing-3);
    }

    .gender-btn {
        flex-direction: row;
        padding: var(--spacing-4);
        justify-content: center;
    }

    .gender-icon {
        font-size: 32px;
    }

    .battle-arena,
    .name-cards {
        flex-direction: column;
        gap: var(--spacing-8);
    }

    .name-card {
        min-height: 160px;
        padding: var(--spacing-8);
    }

    .name-text {
        font-size: 28px;
    }

    .vs-indicator {
        width: 40px;
        height: 40px;
        font-size: 12px;
    }

    .winner-name {
        font-size: 36px;
    }

    .result-actions {
        flex-direction: column;
    }

    .action-btn {
        width: 100%;
        justify-content: center;
    }

    .input-group {
        flex-direction: column;
    }

    .input-group input {
        width: 100%;
    }
}

@media (max-width: 480px) {
    .logo-icon {
        font-size: 48px;
    }

    .logo h1 {
        font-size: 20px;
    }

    .name-text {
        font-size: 24px;
    }

    .winner-name {
        font-size: 32px;
    }

    .winner-card {
        padding: var(--spacing-8);
    }
}

/* Theme */
body.theme-boy {
    --theme-primary: var(--md-primary);
    --theme-primary-variant: var(--md-primary-variant);
}

body.theme-girl {
    --theme-primary: var(--md-secondary);
    --theme-primary-variant: var(--md-secondary-variant);
}