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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: linear-gradient(135deg, #0a0a0a 0%, #1a1a2e 50%, #0a0a0a 100%);
    min-height: 100vh;
    color: #e0e0e0;
}

.container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 20px;
    min-height: 100vh;
}

header {
    text-align: center;
    padding: 30px 0;
    margin-bottom: 20px;
}

header h1 {
    font-size: 2.5rem;
    background: linear-gradient(90deg, #00ff88, #00ffcc);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-shadow: 0 0 30px rgba(0, 255, 136, 0.3);
    margin-bottom: 10px;
}

header p {
    color: #888;
    font-size: 1rem;
}

.category-tabs {
    display: flex;
    justify-content: center;
    gap: 15px;
    margin-bottom: 30px;
    flex-wrap: wrap;
}

.category-tab {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 15px 30px;
    background: rgba(255, 255, 255, 0.03);
    border: 2px solid rgba(0, 255, 136, 0.2);
    border-radius: 15px;
    cursor: pointer;
    transition: all 0.3s ease;
    color: #888;
}

.category-tab:hover {
    background: rgba(0, 255, 136, 0.05);
    border-color: rgba(0, 255, 136, 0.4);
    color: #00ff88;
}

.category-tab.active {
    background: linear-gradient(135deg, rgba(0, 255, 136, 0.15), rgba(0, 255, 204, 0.1));
    border-color: #00ff88;
    color: #00ff88;
    box-shadow: 0 0 30px rgba(0, 255, 136, 0.3);
}

.tab-icon {
    font-size: 1.5rem;
}

.tab-text {
    font-size: 1.1rem;
    font-weight: 600;
}

.category-section {
    animation: fadeIn 0.5s ease;
}

.controls {
    display: flex;
    justify-content: center;
    gap: 30px;
    margin-bottom: 30px;
    flex-wrap: wrap;
}

.control-group {
    display: flex;
    align-items: center;
    gap: 12px;
    background: rgba(255, 255, 255, 0.03);
    padding: 12px 20px;
    border-radius: 15px;
    border: 1px solid rgba(0, 255, 136, 0.15);
}

.control-group label {
    color: #888;
    font-size: 0.9rem;
}

.gender-switcher, .equipment-switcher, .aerobic-switcher, .functional-switcher {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
}

.gender-btn, .equipment-btn, .aerobic-btn, .functional-btn {
    padding: 8px 18px;
    border: 1px solid rgba(0, 255, 136, 0.4);
    background: transparent;
    color: #00ff88;
    border-radius: 20px;
    cursor: pointer;
    font-size: 0.85rem;
    transition: all 0.3s ease;
}

.gender-btn:hover, .equipment-btn:hover, .aerobic-btn:hover, .functional-btn:hover {
    background: rgba(0, 255, 136, 0.1);
}

.gender-btn.active, .equipment-btn.active, .aerobic-btn.active, .functional-btn.active {
    background: #00ff88;
    color: #0a0a0a;
    font-weight: 600;
    box-shadow: 0 0 15px rgba(0, 255, 136, 0.4);
}

.main-content {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: 30px;
    align-items: start;
}

.body-diagram {
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid rgba(0, 255, 136, 0.2);
    border-radius: 20px;
    padding: 30px;
    position: relative;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.5),
                inset 0 1px 0 rgba(255, 255, 255, 0.1);
}

.body-diagram h2 {
    text-align: center;
    margin-bottom: 20px;
    color: #00ff88;
    font-size: 1.3rem;
}

.gender-indicator {
    text-align: center;
    margin-bottom: 15px;
    font-size: 0.9rem;
    color: #888;
}

.gender-indicator span {
    color: #00ff88;
    font-weight: 600;
}

.body-svg {
    display: block;
    margin: 0 auto;
    width: 100%;
    max-width: 280px;
}

.body-svg.female {
    max-width: 250px;
}

.body-part {
    cursor: pointer;
    transition: all 0.3s ease;
    fill: rgba(0, 255, 136, 0.1);
    stroke: #00ff88;
    stroke-width: 2;
}

.body-part:hover {
    fill: rgba(0, 255, 136, 0.3);
    stroke-width: 3;
    filter: drop-shadow(0 0 10px rgba(0, 255, 136, 0.5));
}

.body-part.active {
    fill: rgba(0, 255, 136, 0.4);
    stroke-width: 3;
    filter: drop-shadow(0 0 15px rgba(0, 255, 136, 0.7));
}

.body-outline {
    fill: none;
    stroke: #444;
    stroke-width: 2;
}

.body-label {
    font-size: 12px;
    fill: #aaa;
    pointer-events: none;
    user-select: none;
}

.video-section {
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid rgba(0, 255, 136, 0.2);
    border-radius: 20px;
    padding: 30px;
    min-height: 500px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.5),
                inset 0 1px 0 rgba(255, 255, 255, 0.1);
}

.video-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
    flex-wrap: wrap;
    gap: 15px;
}

.video-title {
    font-size: 1.5rem;
    color: #00ff88;
}

.level-switcher {
    display: flex;
    gap: 10px;
}

.level-btn {
    padding: 8px 20px;
    border: 1px solid rgba(0, 255, 136, 0.5);
    background: transparent;
    color: #00ff88;
    border-radius: 25px;
    cursor: pointer;
    font-size: 0.9rem;
    transition: all 0.3s ease;
}

.level-btn:hover {
    background: rgba(0, 255, 136, 0.1);
}

.level-btn.active {
    background: #00ff88;
    color: #0a0a0a;
    font-weight: 600;
    box-shadow: 0 0 20px rgba(0, 255, 136, 0.4);
}

.current-selection {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
    margin-bottom: 15px;
}

.selection-tag {
    padding: 5px 12px;
    background: rgba(0, 255, 136, 0.1);
    border: 1px solid rgba(0, 255, 136, 0.3);
    border-radius: 15px;
    font-size: 0.8rem;
    color: #00ff88;
}

.video-container {
    position: relative;
    width: 100%;
    padding-bottom: 56.25%;
    background: #000;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 5px 30px rgba(0, 0, 0, 0.5);
}

.video-container iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    border: none;
}

.placeholder {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 400px;
    color: #666;
}

.placeholder svg {
    width: 80px;
    height: 80px;
    margin-bottom: 20px;
    opacity: 0.3;
}

.placeholder p {
    font-size: 1.1rem;
}

.tips {
    margin-top: 20px;
    padding: 15px;
    background: rgba(0, 255, 136, 0.05);
    border-left: 3px solid #00ff88;
    border-radius: 0 10px 10px 0;
}

.tips h3 {
    color: #00ff88;
    margin-bottom: 10px;
    font-size: 1rem;
}

.tips ul {
    list-style: none;
    padding-left: 0;
}

.tips li {
    padding: 5px 0;
    color: #aaa;
    font-size: 0.9rem;
}

.tips li::before {
    content: "•";
    color: #00ff88;
    margin-right: 8px;
}

@media (max-width: 900px) {
    .main-content {
        grid-template-columns: 1fr;
    }

    header h1 {
        font-size: 1.8rem;
    }

    .category-tabs {
        gap: 10px;
    }

    .category-tab {
        padding: 12px 20px;
    }

    .tab-text {
        font-size: 1rem;
    }

    .controls {
        flex-direction: column;
        align-items: center;
    }

    .control-group {
        width: 100%;
        justify-content: center;
    }

    .body-diagram {
        padding: 20px;
    }

    .video-section {
        padding: 20px;
        min-height: auto;
    }

    .video-header {
        flex-direction: column;
        align-items: flex-start;
    }

    .level-switcher {
        width: 100%;
    }

    .level-btn {
        flex: 1;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 15px;
    }

    header {
        padding: 20px 0;
    }

    header h1 {
        font-size: 1.5rem;
    }

    .category-tabs {
        flex-direction: column;
        align-items: stretch;
    }

    .category-tab {
        justify-content: center;
    }

    .control-group {
        flex-direction: column;
        gap: 8px;
    }

    .gender-switcher, .equipment-switcher, .aerobic-switcher, .functional-switcher {
        width: 100%;
    }

    .gender-btn, .equipment-btn, .aerobic-btn, .functional-btn {
        flex: 1;
        text-align: center;
        padding: 8px 12px;
        font-size: 0.8rem;
    }

    .video-title {
        font-size: 1.2rem;
    }

    .level-btn {
        padding: 6px 15px;
        font-size: 0.85rem;
    }
}

.fade-in {
    animation: fadeIn 0.5s ease;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.svg-transition {
    transition: opacity 0.3s ease;
}