/**
 * Apple Design System
 * Based on apple-design skill
 */

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

:root {
    /* Colors - Light Mode */
    --apple-blue: #007AFF;
    --apple-blue-hover: #0051D5;
    --apple-green: #34C759;
    --apple-indigo: #5856D6;
    --apple-orange: #FF9500;
    --apple-pink: #FF2D55;
    --apple-purple: #AF52DE;
    --apple-red: #FF3B30;
    --apple-teal: #5AC8FA;
    --apple-yellow: #FFCC00;

    /* Grays */
    --apple-gray: #8E8E93;
    --apple-gray-2: #AEAEB2;
    --apple-gray-3: #C7C7CC;
    --apple-gray-4: #D1D1D6;
    --apple-gray-5: #E5E5EA;
    --apple-gray-6: #F2F2F7;

    /* Text Colors */
    --text-primary: #1d1d1f;
    --text-secondary: #86868b;

    /* Backgrounds */
    --apple-bg-primary: #FFFFFF;
    --apple-bg-secondary: #F2F2F7;

    /* Typography */
    --font-regular: 400;
    --font-medium: 500;
    --font-semibold: 600;
    --font-bold: 700;

    /* Spacing (8-point grid) */
    --spacing-xs: 4px;
    --spacing-sm: 8px;
    --spacing-md: 16px;
    --spacing-lg: 24px;
    --spacing-xl: 32px;
    --spacing-2xl: 48px;
    --spacing-3xl: 64px;
    --spacing-4xl: 96px;
    --spacing-5xl: 128px;

    /* Border Radius */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 20px;
    --radius-2xl: 24px;
    --radius-full: 9999px;

    /* Shadows */
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.07);
    --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px rgba(0, 0, 0, 0.1);
    --shadow-2xl: 0 25px 50px rgba(0, 0, 0, 0.15);

    /* Animations */
    --ease-in-out: cubic-bezier(0.42, 0, 0.58, 1);
    --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
    --ease-in: cubic-bezier(0.32, 0, 0.67, 0);
    --ease-spring: cubic-bezier(0.68, -0.55, 0.265, 1.55);

    --duration-fast: 200ms;
    --duration-normal: 300ms;
    --duration-slow: 500ms;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background: var(--apple-bg-primary);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    /* PWA mobile readability - minimum 16px base font */
    font-size: 16px;
    -webkit-text-size-adjust: 100%;
    text-size-adjust: 100%;
}

/* PWA Touch Target & Mobile Readability */
@media screen and (max-width: 768px) {
    body {
        font-size: 16px;
    }

    /* Ensure minimum touch target size (44x44px) */
    button,
    .btn,
    input[type="submit"],
    input[type="button"],
    a.menu-item,
    a.menu-btn {
        min-height: 44px;
        min-width: 44px;
    }

    /* Ensure readable input fields */
    input[type="text"],
    input[type="email"],
    input[type="password"],
    input[type="number"],
    input[type="tel"],
    select,
    textarea {
        font-size: 16px !important; /* Prevents iOS zoom on focus */
    }
}

html {
    scroll-behavior: smooth;
}

/* ==========================================
   Navigation
   ========================================== */
.navbar {
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(20px) saturate(180%);
    -webkit-backdrop-filter: blur(20px) saturate(180%);
    border-bottom: 1px solid rgba(0, 0, 0, 0.1);
    padding: 12px 24px;
    position: sticky;
    top: 0;
    z-index: 1000;
    transition: all var(--duration-normal) var(--ease-out);
}

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

.navbar-brand {
    font-size: 20px;
    font-weight: var(--font-bold);
    color: var(--text-primary);
    text-decoration: none;
}

.navbar-menu {
    display: flex;
    gap: var(--spacing-lg);
    list-style: none;
}

.navbar-menu a {
    color: var(--text-primary);
    text-decoration: none;
    font-weight: var(--font-regular);
    font-size: 15px;
    transition: color var(--duration-normal) var(--ease-out);
}

.navbar-menu a:hover {
    color: var(--apple-blue);
}

.navbar-user {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    font-size: 14px;
    color: var(--text-secondary);
}

/* ==========================================
   Hero Section
   ========================================== */
.hero {
    min-height: 80vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    padding: var(--spacing-4xl) var(--spacing-lg);
    background: linear-gradient(180deg, #f5f5f7 0%, #ffffff 100%);
}

.hero h1 {
    font-size: clamp(48px, 8vw, 80px);
    font-weight: var(--font-bold);
    line-height: 1.1;
    margin-bottom: var(--spacing-lg);
    letter-spacing: -0.02em;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero p {
    font-size: clamp(18px, 3vw, 24px);
    color: var(--apple-gray);
    max-width: 600px;
    line-height: 1.5;
    margin-bottom: var(--spacing-2xl);
}

/* ==========================================
   Container
   ========================================== */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: var(--spacing-3xl) var(--spacing-lg);
}

.container-sm {
    max-width: 480px;
}

.container-md {
    max-width: 800px;
}

/* ==========================================
   Buttons
   ========================================== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 12px 24px;
    border-radius: var(--radius-full);
    font-weight: var(--font-semibold);
    font-size: 17px;
    border: none;
    cursor: pointer;
    transition: all var(--duration-normal) var(--ease-out);
    text-decoration: none;
}

.btn-primary {
    background: var(--apple-blue);
    color: white;
}

.btn-primary:hover {
    background: var(--apple-blue-hover);
    transform: scale(1.02);
}

.btn-secondary {
    background: var(--apple-gray-6);
    color: var(--text-primary);
}

.btn-secondary:hover {
    background: var(--apple-gray-5);
}

.btn-outline {
    background: transparent;
    color: var(--apple-blue);
    border: 2px solid var(--apple-blue);
}

.btn-outline:hover {
    background: var(--apple-blue);
    color: white;
    transform: scale(1.02);
}

.btn-danger {
    background: var(--apple-red);
    color: white;
}

.btn-danger:hover {
    background: #D70015;
}

.btn-lg {
    padding: 16px 32px;
    font-size: 18px;
}

.btn-block {
    width: 100%;
}

.btn-group {
    display: flex;
    gap: var(--spacing-md);
    flex-wrap: wrap;
    justify-content: center;
}

/* ==========================================
   Cards
   ========================================== */
.card {
    background: var(--apple-bg-primary);
    border-radius: var(--radius-xl);
    padding: var(--spacing-xl);
    box-shadow: var(--shadow-lg);
    transition: all var(--duration-normal) var(--ease-out);
}

.card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-2xl);
}

.card-static:hover {
    transform: none;
    box-shadow: var(--shadow-lg);
}

.card-glass {
    background: rgba(255, 255, 255, 0.7);
    backdrop-filter: blur(20px) saturate(180%);
    -webkit-backdrop-filter: blur(20px) saturate(180%);
    border: 1px solid rgba(255, 255, 255, 0.3);
}

.card-header {
    margin-bottom: var(--spacing-lg);
    padding-bottom: var(--spacing-md);
    border-bottom: 1px solid var(--apple-gray-5);
}

/* ==========================================
   Forms
   ========================================== */
.form-group {
    margin-bottom: var(--spacing-lg);
}

.form-label {
    display: block;
    margin-bottom: var(--spacing-sm);
    font-size: 14px;
    font-weight: var(--font-medium);
    color: var(--text-secondary);
}

.form-control {
    width: 100%;
    padding: 14px 16px;
    font-size: 17px;
    font-family: inherit;
    border: 1px solid var(--apple-gray-4);
    border-radius: var(--radius-md);
    background: var(--apple-bg-primary);
    transition: all var(--duration-normal) var(--ease-out);
    -webkit-appearance: none;
}

.form-control:focus {
    outline: none;
    border-color: var(--apple-blue);
    box-shadow: 0 0 0 3px rgba(0, 122, 255, 0.15);
}

.form-control::placeholder {
    color: var(--apple-gray-3);
}

textarea.form-control {
    min-height: 120px;
    resize: vertical;
    line-height: 1.5;
}

select.form-control {
    cursor: pointer;
}

/* ==========================================
   Alerts
   ========================================== */
.alert {
    padding: 16px 20px;
    border-radius: var(--radius-md);
    margin-bottom: var(--spacing-lg);
    font-size: 15px;
}

.alert-success {
    background: rgba(52, 199, 89, 0.12);
    color: #248A3D;
    border: 1px solid rgba(52, 199, 89, 0.2);
}

.alert-error {
    background: rgba(255, 59, 48, 0.12);
    color: #D70015;
    border: 1px solid rgba(255, 59, 48, 0.2);
}

.alert-warning {
    background: rgba(255, 149, 0, 0.12);
    color: #C93400;
    border: 1px solid rgba(255, 149, 0, 0.2);
}

/* ==========================================
   Grid & Layout
   ========================================== */
.row {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-lg);
}

.col-2 {
    flex: 1;
    min-width: 250px;
}

.grid {
    display: grid;
    gap: var(--spacing-lg);
}

.grid-2 {
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
}

.grid-3 {
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}

.grid-4 {
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
}

/* ==========================================
   Stats Cards
   ========================================== */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
}

.stat-card {
    background: var(--apple-bg-primary);
    border-radius: var(--radius-xl);
    padding: var(--spacing-lg);
    box-shadow: var(--shadow-md);
}

.stat-value {
    font-size: 36px;
    font-weight: var(--font-bold);
    color: var(--text-primary);
    margin-bottom: 4px;
}

.stat-label {
    font-size: 14px;
    color: var(--text-secondary);
}

/* ==========================================
   Progress Bar
   ========================================== */
.progress {
    height: 8px;
    background: var(--apple-gray-5);
    border-radius: 4px;
    overflow: hidden;
    margin: 12px 0;
}

.progress-bar {
    height: 100%;
    background: linear-gradient(90deg, var(--apple-blue), var(--apple-indigo));
    border-radius: 4px;
    transition: width var(--duration-slow) var(--ease-out);
}

/* ==========================================
   Tables
   ========================================== */
.table-wrapper {
    overflow-x: auto;
    border-radius: var(--radius-md);
}

table {
    width: 100%;
    border-collapse: collapse;
}

th, td {
    padding: 14px 16px;
    text-align: left;
    border-bottom: 1px solid var(--apple-gray-5);
}

th {
    background: var(--apple-gray-6);
    font-weight: var(--font-semibold);
    font-size: 13px;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

td {
    font-size: 15px;
}

tr:hover td {
    background: var(--apple-gray-6);
}

/* ==========================================
   Combination Matrix Table
   ========================================== */
.matrix-table {
    font-size: 12px;
}

.matrix-table th,
.matrix-table td {
    padding: 8px 6px;
    text-align: center;
    min-width: 70px;
}

.matrix-table th {
    background: var(--apple-blue);
    color: white;
    font-size: 11px;
    position: sticky;
    top: 0;
    text-transform: none;
    letter-spacing: normal;
}

.matrix-table th.row-header {
    background: var(--apple-indigo);
    position: sticky;
    left: 0;
    z-index: 2;
}

.matrix-table th.corner {
    position: sticky;
    top: 0;
    left: 0;
    z-index: 3;
    background: var(--text-primary);
}

.matrix-table .cell-registered {
    background: rgba(52, 199, 89, 0.15);
    cursor: pointer;
    transition: var(--duration-fast) var(--ease-out);
}

.matrix-table .cell-registered:hover {
    background: rgba(52, 199, 89, 0.3);
}

.matrix-table .cell-ai-generated {
    background: rgba(0, 122, 255, 0.15);
    cursor: pointer;
    transition: var(--duration-fast) var(--ease-out);
}

.matrix-table .cell-ai-generated:hover {
    background: rgba(0, 122, 255, 0.3);
}

.matrix-table .cell-ai-generated .character-name {
    color: #0051D5;
}

.matrix-table .cell-empty {
    background: var(--apple-bg-primary);
}

.matrix-table .cell-empty:hover {
    background: var(--apple-gray-6);
}

.matrix-table .cell-diagonal {
    background: var(--apple-gray-5);
    color: var(--apple-gray);
}

.matrix-table .character-name {
    font-size: 10px;
    font-weight: var(--font-semibold);
    color: #248A3D;
    word-break: break-all;
}

.matrix-table .add-btn {
    color: var(--apple-blue);
    text-decoration: none;
    font-size: 18px;
    font-weight: 300;
}

/* ==========================================
   Legend
   ========================================== */
.legend {
    display: flex;
    justify-content: center;
    gap: var(--spacing-lg);
    margin-top: var(--spacing-lg);
    font-size: 13px;
}

.legend-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.legend-dot {
    width: 12px;
    height: 12px;
    border-radius: 3px;
}

.legend-dot.registered { background: rgba(52, 199, 89, 0.3); }
.legend-dot.ai-generated { background: rgba(0, 122, 255, 0.3); }
.legend-dot.empty { background: var(--apple-bg-primary); border: 1px solid var(--apple-gray-4); }
.legend-dot.diagonal { background: var(--apple-gray-5); }

/* ==========================================
   Feature Cards (for user page)
   ========================================== */
.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-lg);
}

.feature-card {
    background: var(--apple-bg-primary);
    border-radius: var(--radius-xl);
    padding: var(--spacing-xl);
    text-align: center;
    box-shadow: var(--shadow-md);
    transition: all var(--duration-normal) var(--ease-out);
}

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

.feature-icon {
    width: 60px;
    height: 60px;
    background: linear-gradient(135deg, var(--apple-blue), var(--apple-indigo));
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto var(--spacing-md);
    font-size: 28px;
}

.feature-card h3 {
    font-size: 18px;
    font-weight: var(--font-semibold);
    margin-bottom: var(--spacing-sm);
}

.feature-card p {
    color: var(--text-secondary);
    font-size: 15px;
    line-height: 1.5;
}

/* ==========================================
   Section
   ========================================== */
.section {
    padding: var(--spacing-4xl) 0;
}

.section-title {
    font-size: clamp(32px, 5vw, 48px);
    font-weight: var(--font-bold);
    text-align: center;
    margin-bottom: var(--spacing-md);
    letter-spacing: -0.02em;
}

.section-subtitle {
    font-size: clamp(16px, 2.5vw, 20px);
    color: var(--text-secondary);
    text-align: center;
    max-width: 600px;
    margin: 0 auto var(--spacing-2xl);
    line-height: 1.5;
}

/* ==========================================
   Navigation Links
   ========================================== */
.nav-links {
    display: flex;
    justify-content: center;
    gap: var(--spacing-lg);
    margin-top: var(--spacing-lg);
}

.nav-links a {
    color: var(--apple-blue);
    text-decoration: none;
    font-size: 15px;
    font-weight: var(--font-medium);
    transition: color var(--duration-fast) var(--ease-out);
}

.nav-links a:hover {
    color: var(--apple-blue-hover);
    text-decoration: underline;
}

/* ==========================================
   Image Preview
   ========================================== */
.preview-image {
    max-width: 200px;
    margin-top: 12px;
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-sm);
}

/* ==========================================
   Footer
   ========================================== */
.footer {
    background: var(--apple-gray-6);
    padding: var(--spacing-2xl) var(--spacing-lg);
    text-align: center;
    border-top: 1px solid var(--apple-gray-5);
}

.footer p {
    color: var(--text-secondary);
    font-size: 14px;
}

/* ==========================================
   Typography Utilities
   ========================================== */
.text-center { text-align: center; }
.text-muted { color: var(--text-secondary); }
.text-sm { font-size: 14px; }
.text-lg { font-size: 18px; }

h1, h2, h3, h4 {
    font-weight: var(--font-semibold);
    letter-spacing: -0.02em;
    line-height: 1.2;
}

h1 { font-size: 32px; }
h2 { font-size: 24px; }
h3 { font-size: 20px; }

/* ==========================================
   Responsive
   ========================================== */
@media (max-width: 768px) {
    .navbar-inner {
        flex-wrap: wrap;
        padding: 10px 15px;
    }

    .navbar-brand {
        font-size: 16px;
    }

    .navbar-menu {
        order: 3;
        width: 100%;
        margin-top: 10px;
        padding-top: 10px;
        border-top: 1px solid rgba(255,255,255,0.2);
        justify-content: center;
        gap: 5px;
    }

    .navbar-menu a {
        font-size: 12px;
        padding: 6px 10px;
    }

    .navbar-user {
        font-size: 12px;
    }

    .navbar-user .btn {
        padding: 6px 10px !important;
        font-size: 12px !important;
    }

    .hero h1 {
        font-size: 36px;
    }

    .hero p {
        font-size: 16px;
    }

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

    .row {
        flex-direction: column;
    }

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

    .feature-grid {
        grid-template-columns: 1fr;
    }

    .btn-group {
        flex-direction: column;
        width: 100%;
    }

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