* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

/* Light Theme (Default) */
:root,
[data-theme="light"] {
    --primary: #2563eb;
    --primary-hover: #1d4ed8;
    --primary-light: #eff6ff;
    --bg: #f8fafc;
    --card-bg: #ffffff;
    --text: #1e293b;
    --text-muted: #64748b;
    --border: #e2e8f0;
    --radius: 12px;
    --shadow: 0 1px 3px rgba(0,0,0,0.1);
    --shadow-hover: 0 4px 12px rgba(0,0,0,0.15);
    --success: #22c55e;
    --success-bg: #f0fdf4;
    --success-border: #86efac;
    --error: #dc2626;
    --error-bg: #fef2f2;
    --error-border: #fca5a5;
    --warning-bg: #fffbeb;
    --warning-border: #fcd34d;
    --input-bg: var(--bg);
}

/* Dark Theme */
[data-theme="dark"] {
    --primary: #3b82f6;
    --primary-hover: #60a5fa;
    --primary-light: #1e3a5f;
    --bg: #0f172a;
    --card-bg: #1e293b;
    --text: #f1f5f9;
    --text-muted: #94a3b8;
    --border: #334155;
    --shadow: 0 1px 3px rgba(0,0,0,0.3);
    --shadow-hover: 0 4px 12px rgba(0,0,0,0.4);
    --success: #4ade80;
    --success-bg: #14532d;
    --success-border: #22c55e;
    --error: #f87171;
    --error-bg: #7f1d1d;
    --error-border: #dc2626;
    --warning-bg: #78350f;
    --warning-border: #f59e0b;
    --input-bg: #0f172a;
}

/* Sepia Theme */
[data-theme="sepia"] {
    --primary: #92400e;
    --primary-hover: #b45309;
    --primary-light: #fef3c7;
    --bg: #fdf6e3;
    --card-bg: #fefcf8;
    --text: #44403c;
    --text-muted: #78716c;
    --border: #d6d3d1;
    --shadow: 0 1px 3px rgba(0,0,0,0.08);
    --shadow-hover: 0 4px 12px rgba(0,0,0,0.12);
    --success: #15803d;
    --success-bg: #dcfce7;
    --success-border: #86efac;
    --error: #b91c1c;
    --error-bg: #fee2e2;
    --error-border: #fca5a5;
    --warning-bg: #fef9c3;
    --warning-border: #fcd34d;
    --input-bg: #fefcf8;
}

/* High Contrast Theme */
[data-theme="contrast"] {
    --primary: #0066cc;
    --primary-hover: #0088ff;
    --primary-light: #cce5ff;
    --bg: #000000;
    --card-bg: #1a1a1a;
    --text: #ffffff;
    --text-muted: #cccccc;
    --border: #666666;
    --shadow: 0 1px 3px rgba(255,255,255,0.1);
    --shadow-hover: 0 4px 12px rgba(255,255,255,0.15);
    --success: #00ff00;
    --success-bg: #003300;
    --success-border: #00cc00;
    --error: #ff0000;
    --error-bg: #330000;
    --error-border: #cc0000;
    --warning-bg: #332200;
    --warning-border: #ffcc00;
    --input-bg: #000000;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    line-height: 1.6;
    color: var(--text);
    background: var(--bg);
    -webkit-font-smoothing: antialiased;
    transition: background 0.3s, color 0.3s;
}

header {
    background: var(--card-bg);
    border-bottom: 1px solid var(--border);
    padding: 1rem 1rem;
    position: sticky;
    top: 0;
    z-index: 100;
    transition: background 0.3s, border-color 0.3s;
}

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

.logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    text-decoration: none;
    color: var(--text);
}

.logo-icon {
    width: 36px;
    height: 36px;
    background: var(--primary);
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    font-weight: 700;
    font-size: 1.2rem;
    transition: background 0.3s;
}

.logo-text {
    font-size: 1.25rem;
    font-weight: 700;
}

.header-right {
    display: flex;
    align-items: center;
    gap: 1.5rem;
}

.nav-links {
    display: flex;
    gap: 1.5rem;
}

.nav-links a {
    color: var(--text-muted);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.2s;
}

.nav-links a:hover {
    color: var(--primary);
}

.theme-switcher {
    display: flex;
    gap: 0.5rem;
    align-items: center;
}

.theme-btn {
    width: 32px;
    height: 32px;
    border-radius: 6px;
    border: 2px solid var(--border);
    cursor: pointer;
    transition: all 0.2s;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.9rem;
}

.theme-btn:hover {
    border-color: var(--primary);
    transform: scale(1.1);
}

.theme-btn.active {
    border-color: var(--primary);
    background: var(--primary-light);
}

.theme-btn[data-theme="light"] { background: linear-gradient(135deg, #f8fafc 50%, #e2e8f0 50%); }
.theme-btn[data-theme="dark"] { background: linear-gradient(135deg, #1e293b 50%, #0f172a 50%); }
.theme-btn[data-theme="sepia"] { background: linear-gradient(135deg, #fefcf8 50%, #d6d3d1 50%); }
.theme-btn[data-theme="contrast"] { background: linear-gradient(135deg, #ffffff 50%, #000000 50%); border-color: #666; }

main {
    max-width: 1200px;
    margin: 0 auto;
    padding: 3rem 1rem;
}

.hero {
    text-align: center;
    padding: 4rem 1rem;
    max-width: 700px;
    margin: 0 auto 3rem;
}

.hero h1 {
    font-size: 2.5rem;
    font-weight: 800;
    color: var(--text);
    margin-bottom: 1rem;
    letter-spacing: -0.02em;
}

.hero p {
    font-size: 1.2rem;
    color: var(--text-muted);
    max-width: 540px;
    margin: 0 auto;
}

.section-title {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text);
    margin-bottom: 1.5rem;
}

.tools-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
    gap: 1rem;
    margin-bottom: 3rem;
}

.tool-card {
    background: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 1.5rem;
    text-decoration: none;
    color: inherit;
    transition: all 0.2s ease;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.tool-card:hover {
    border-color: var(--primary);
    box-shadow: var(--shadow-hover);
    transform: translateY(-2px);
}

.tool-icon {
    width: 44px;
    height: 44px;
    background: var(--primary-light);
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.3rem;
    color: var(--primary);
    transition: background 0.3s, color 0.3s;
}

.tool-card h3 {
    color: var(--text);
    font-size: 1.1rem;
    font-weight: 600;
}

.tool-card p {
    color: var(--text-muted);
    font-size: 0.9rem;
    line-height: 1.5;
}

.features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.5rem;
    margin: 4rem 0;
}

.feature {
    background: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 1.5rem;
    transition: background 0.3s, border-color 0.3s;
}

.feature-icon {
    width: 48px;
    height: 48px;
    background: var(--success-bg);
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.4rem;
    margin-bottom: 1rem;
    transition: background 0.3s;
}

.feature h3 {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: var(--text);
}

.feature p {
    color: var(--text-muted);
    font-size: 0.9rem;
}

footer {
    background: var(--card-bg);
    border-top: 1px solid var(--border);
    padding: 2rem 1rem;
    text-align: center;
    color: var(--text-muted);
    font-size: 0.875rem;
    transition: background 0.3s, border-color 0.3s;
}

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

footer a:hover {
    text-decoration: underline;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.625rem 1.25rem;
    border-radius: 8px;
    font-weight: 500;
    font-size: 0.95rem;
    cursor: pointer;
    transition: all 0.2s;
    border: none;
    text-decoration: none;
}

.btn-primary {
    background: var(--primary);
    color: #fff;
}

.btn-primary:hover {
    background: var(--primary-hover);
}

.btn-secondary {
    background: var(--bg);
    color: var(--text);
    border: 1px solid var(--border);
}

.btn-secondary:hover {
    background: var(--border);
}

.btn:active {
    transform: scale(0.98);
}

/* Tool Page Styles */
.tool-header {
    margin-bottom: 2rem;
}
.tool-header h1 {
    font-size: 1.75rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}
.tool-header p {
    color: var(--text-muted);
}

.back-link {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--primary);
    text-decoration: none;
    font-weight: 500;
    margin-bottom: 1.5rem;
    transition: color 0.2s;
}
.back-link:hover {
    text-decoration: underline;
}

.card {
    background: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 1.5rem;
    margin-bottom: 1rem;
    transition: background 0.3s, border-color 0.3s;
}

.card-title {
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 0.75rem;
}

textarea, input[type="text"], input[type="number"] {
    width: 100%;
    padding: 0.875rem 1rem;
    border: 1px solid var(--border);
    border-radius: 8px;
    font-family: 'SF Mono', Monaco, 'Cascadia Code', 'Roboto Mono', monospace;
    font-size: 0.9rem;
    background: var(--input-bg);
    color: var(--text);
    transition: background 0.3s, border-color 0.3s, color 0.3s;
}

textarea:focus, input[type="text"]:focus, input[type="number"]:focus {
    outline: none;
    border-color: var(--primary);
}

textarea {
    resize: vertical;
}

.btn-group {
    display: flex;
    gap: 0.5rem;
    margin-top: 1rem;
    flex-wrap: wrap;
}

.output-box {
    margin-top: 1rem;
    padding: 1rem;
    border-radius: 8px;
    font-family: 'SF Mono', Monaco, monospace;
    font-size: 0.9rem;
    white-space: pre-wrap;
    word-break: break-all;
    max-height: 400px;
    overflow-y: auto;
    background: var(--bg);
    border: 1px solid var(--border);
    color: var(--text);
    transition: background 0.3s, border-color 0.3s, color 0.3s;
}

.output-box.success {
    background: var(--success-bg);
    border-color: var(--success-border);
    color: var(--text);
}

.output-box.error {
    background: var(--error-bg);
    border-color: var(--error-border);
    color: var(--error);
}

.badge {
    display: inline-block;
    padding: 0.25rem 0.5rem;
    border-radius: 4px;
    font-size: 0.75rem;
    font-weight: 600;
}

.badge-success {
    background: var(--success-bg);
    color: var(--success);
    border: 1px solid var(--success-border);
}

.badge-error {
    background: var(--error-bg);
    color: var(--error);
    border: 1px solid var(--error-border);
}

.hash-result {
    margin-top: 1rem;
}
.hash-result label {
    font-weight: 600;
    color: var(--text-muted);
    font-size: 0.85rem;
    display: block;
    margin-bottom: 0.25rem;
}
.hash-result code {
    display: block;
    font-family: 'SF Mono', Monaco, monospace;
    font-size: 0.85rem;
    word-break: break-all;
    background: var(--bg);
    padding: 0.75rem;
    border-radius: 6px;
    border: 1px solid var(--border);
    color: var(--text);
    transition: background 0.3s, border-color 0.3s, color 0.3s;
}

.jwt-parts {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1rem;
    margin-top: 1rem;
}
.jwt-part {
    background: var(--bg);
    border-radius: 8px;
    padding: 1rem;
    transition: background 0.3s;
}
.jwt-part h4 {
    font-size: 0.9rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: var(--text);
}
.jwt-part pre {
    background: var(--card-bg);
    padding: 0.75rem;
    border-radius: 6px;
    overflow-x: auto;
    font-size: 0.85rem;
    border: 1px solid var(--border);
    color: var(--text);
    transition: background 0.3s, border-color 0.3s, color 0.3s;
}

.jwt-info {
    margin-top: 1rem;
    padding: 1rem;
    background: var(--success-bg);
    border: 1px solid var(--success-border);
    border-radius: 8px;
    font-size: 0.9rem;
    color: var(--text);
    transition: background 0.3s, border-color 0.3s;
}

.error-box {
    padding: 1rem;
    background: var(--error-bg);
    border: 1px solid var(--error-border);
    border-radius: 8px;
    color: var(--error);
    margin-top: 1rem;
    transition: background 0.3s, border-color 0.3s;
}

.match-highlight {
    background: var(--warning-bg);
    padding: 0.125rem 0.25rem;
    border-radius: 3px;
    border: 1px solid var(--warning-border);
}

input[type="color"] {
    width: 60px;
    height: 44px;
    border: 2px solid var(--border);
    border-radius: 8px;
    cursor: pointer;
    padding: 2px;
    background: var(--card-bg);
}

input[type="color"]::-webkit-color-swatch-wrapper {
    padding: 0;
}

input[type="color"]::-webkit-color-swatch {
    border: none;
    border-radius: 4px;
}

.color-preview {
    height: 44px;
    border-radius: 8px;
    border: 1px solid var(--border);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: 0.9rem;
    color: #fff;
    text-shadow: 0 1px 2px rgba(0,0,0,0.3);
    transition: background 0.3s, border-color 0.3s;
}

.uuid-display, .password-display {
    font-family: 'SF Mono', Monaco, monospace;
    font-size: 1.3rem;
    padding: 1.5rem;
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: 8px;
    text-align: center;
    letter-spacing: 1px;
    color: var(--text);
    transition: background 0.3s, border-color 0.3s, color 0.3s;
}

.strength-meter {
    height: 8px;
    background: var(--border);
    border-radius: 4px;
    margin-top: 1rem;
    overflow: hidden;
    transition: background 0.3s;
}

.strength-bar {
    height: 100%;
    border-radius: 4px;
    transition: width 0.3s, background 0.3s;
}

.result-item {
    background: var(--bg);
    padding: 1rem;
    border-radius: 8px;
    text-align: center;
    border: 1px solid var(--border);
    transition: background 0.3s, border-color 0.3s;
}
.result-item label {
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
    display: block;
    margin-bottom: 0.5rem;
}
.result-item code {
    font-family: 'SF Mono', Monaco, monospace;
    font-size: 0.9rem;
    color: var(--text);
}

.cron-display {
    font-family: 'SF Mono', Monaco, monospace;
    font-size: 1.5rem;
    background: var(--bg);
    padding: 1.5rem;
    border-radius: 8px;
    text-align: center;
    border: 1px solid var(--border);
    margin: 1rem 0;
    color: var(--text);
    transition: background 0.3s, border-color 0.3s, color 0.3s;
}

.cron-description {
    padding: 1rem;
    background: var(--success-bg);
    border: 1px solid var(--success-border);
    border-radius: 8px;
    color: var(--text);
    font-size: 0.9rem;
    transition: background 0.3s, border-color 0.3s;
}

.preset-btn {
    padding: 0.75rem 1rem;
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: 8px;
    cursor: pointer;
    text-align: left;
    transition: all 0.2s;
    color: var(--text);
}
.preset-btn:hover {
    border-color: var(--primary);
    background: var(--primary-light);
}
.preset-btn strong {
    display: block;
    margin-bottom: 0.25rem;
    font-size: 0.9rem;
}
.preset-btn code {
    font-family: 'SF Mono', Monaco, monospace;
    font-size: 0.8rem;
    color: var(--text-muted);
}

.flag-label {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    cursor: pointer;
    font-size: 0.9rem;
    color: var(--text);
}

@media (max-width: 768px) {
    .header-content {
        flex-direction: column;
        gap: 1rem;
    }

    .hero h1 {
        font-size: 1.8rem;
    }

    .hero p {
        font-size: 1rem;
    }

    .nav-links {
        gap: 1rem;
    }

    main {
        padding: 2rem 1rem;
    }
}