:root {
    --bg-primary: #000000;
    --bg-secondary: #111111;
    --accent: #FFD700;
    --text-primary: #FFFFFF;
    --text-secondary: #B0B0B0;
    --separator: #333333;
    --card-bg: #1A1A1A;
    --error: #FF4444;
    --success: #44FF44;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    min-height: 100vh;
}

.header {
    background: var(--bg-secondary);
    padding: 20px;
    text-align: center;
    border-bottom: 1px solid var(--separator);
}

.header h1 {
    color: var(--accent);
    font-size: 1.5rem;
}

.header p {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-top: 5px;
}

.nav {
    display: flex;
    justify-content: center;
    gap: 10px;
    padding: 15px;
    background: var(--bg-secondary);
    flex-wrap: wrap;
}

.nav a {
    color: var(--text-primary);
    text-decoration: none;
    padding: 10px 20px;
    border: 1px solid var(--separator);
    border-radius: 6px;
    transition: all 0.2s;
}

.nav a:hover, .nav a.active {
    background: var(--accent);
    color: var(--bg-primary);
    border-color: var(--accent);
}

.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 20px;
}

.section-title {
    color: var(--accent);
    font-size: 1.2rem;
    margin-bottom: 15px;
    padding-bottom: 10px;
    border-bottom: 1px solid var(--separator);
}

.card {
    background: var(--card-bg);
    border-radius: 8px;
    padding: 15px;
    margin-bottom: 15px;
    border: 1px solid var(--separator);
}

.card h3 {
    color: var(--text-primary);
    margin-bottom: 10px;
}

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

.card .meta {
    color: var(--accent);
    font-size: 0.8rem;
    margin-top: 10px;
}

.loading {
    text-align: center;
    padding: 40px;
    color: var(--text-secondary);
}

.empty {
    text-align: center;
    padding: 40px;
    color: var(--text-secondary);
}

.btn {
    display: inline-block;
    padding: 12px 24px;
    background: var(--accent);
    color: var(--bg-primary);
    border: none;
    border-radius: 6px;
    font-size: 1rem;
    font-weight: bold;
    cursor: pointer;
    transition: all 0.2s;
    text-decoration: none;
}

.btn:hover {
    opacity: 0.9;
    transform: translateY(-1px);
}

.btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.btn-outline {
    background: transparent;
    border: 1px solid var(--accent);
    color: var(--accent);
}

.btn-outline:hover {
    background: var(--accent);
    color: var(--bg-primary);
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    color: var(--text-secondary);
    margin-bottom: 8px;
    font-size: 0.9rem;
}

.form-group input {
    width: 100%;
    padding: 12px;
    background: var(--bg-secondary);
    border: 1px solid var(--separator);
    border-radius: 6px;
    color: var(--text-primary);
    font-size: 1rem;
}

.form-group input:focus {
    outline: none;
    border-color: var(--accent);
}

.form-group .error {
    color: var(--error);
    font-size: 0.8rem;
    margin-top: 5px;
}

.alert {
    padding: 15px;
    border-radius: 6px;
    margin-bottom: 20px;
}

.alert-error {
    background: rgba(255, 68, 68, 0.1);
    border: 1px solid var(--error);
    color: var(--error);
}

.alert-success {
    background: rgba(68, 255, 68, 0.1);
    border: 1px solid var(--success);
    color: var(--success);
}

.login-container {
    max-width: 400px;
    margin: 40px auto;
    padding: 30px;
    background: var(--card-bg);
    border-radius: 8px;
    border: 1px solid var(--separator);
}

.login-container h2 {
    text-align: center;
    color: var(--accent);
    margin-bottom: 30px;
}

.category-tag {
    display: inline-block;
    padding: 4px 10px;
    background: rgba(255, 215, 0, 0.1);
    color: var(--accent);
    border-radius: 4px;
    font-size: 0.75rem;
    margin-right: 5px;
    margin-bottom: 5px;
}

.video-card {
    position: relative;
}

.video-card .thumbnail {
    width: 100%;
    aspect-ratio: 16/9;
    background: var(--bg-secondary);
    border-radius: 6px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 10px;
}

.video-card .play-icon {
    font-size: 3rem;
}

.program-day {
    display: flex;
    align-items: flex-start;
    gap: 15px;
}

.program-day .day-number {
    min-width: 50px;
    height: 50px;
    background: var(--accent);
    color: var(--bg-primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
}

.program-day .day-content {
    flex: 1;
}

.analysis-result {
    background: var(--bg-secondary);
    padding: 15px;
    border-radius: 6px;
    margin-top: 10px;
    white-space: pre-wrap;
    font-size: 0.9rem;
    line-height: 1.6;
}

@media (max-width: 600px) {
    .nav {
        flex-direction: column;
    }
    .nav a {
        text-align: center;
    }
    .container {
        padding: 15px;
    }
    .login-container {
        margin: 20px;
        padding: 20px;
    }
}