:root {
    --tesla-red: #e82127;
    --bg-black: #050505;
    --card-bg: rgba(20, 20, 20, 0.7);
    --card-hover: rgba(30, 30, 30, 0.8);
    --text-primary: #ffffff;
    --text-secondary: #a1a1a1;
    --accent-glow: rgba(232, 33, 39, 0.3);
    --transition: all 0.4s cubic-bezier(0.16, 1, 0.3, 1);
    --glass-bg: rgba(10, 10, 10, 0.8);
    --glass-border: rgba(255, 255, 255, 0.08);
}

* {
    box-sizing: border-box;
    -webkit-tap-highlight-color: transparent;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background-color: var(--bg-black);
    color: var(--text-primary);
    margin: 0;
    padding: 0;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    align-items: center;
    overflow-x: hidden;
    width: 100vw;
    background-image: radial-gradient(circle at 50% -20%, var(--accent-glow) 0%, transparent 50%),
        radial-gradient(circle at 0% 100%, rgba(20, 20, 20, 0.5) 0%, transparent 40%);
    line-height: 1.4;
}

/* App Header */
.app-header {
    width: 100%;
    padding: 20px;
    display: flex;
    flex-direction: column;
    align-items: center;
    position: relative;
    z-index: 10;
}

.app-header h1 {
    font-size: 24px;
    font-weight: 700;
    letter-spacing: 6px;
    text-transform: uppercase;
    margin: 0;
    background: linear-gradient(135deg, #fff 0%, #a1a1a1 100%);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.app-header .subtitle {
    font-size: 16px;
    color: var(--text-secondary);
    margin-top: 8px;
    letter-spacing: 2px;
    font-weight: 500;
}

/* Layout */
.main-content {
    width: 100%;
    max-width: 600px;
    padding: 0 20px 20px;
    display: flex;
    flex-direction: column;
    gap: 14px;
    position: relative;
    z-index: 5;
}

.card {
    background: var(--card-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--glass-border);
    border-radius: 16px;
    padding: 6px 12px 6px 12px;
    transition: var(--transition);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
}

.card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    cursor: pointer;
    padding: 4px 0;
}

.card-title {
    font-size: 16px;
    font-weight: 600;
    color: var(--text-primary);
    letter-spacing: 1px;
}

.guide-steps {
    list-style: none;
    padding: 0;
    margin: 8px 0 0 0;
    font-size: 14px;
    color: var(--text-secondary);
    transition: var(--transition);
    max-height: 100px;
    opacity: 1;
    overflow: hidden;
}

.guide-steps.collapsed {
    max-height: 0;
    opacity: 0;
    margin-top: 0;
}

.guide-steps li {
    margin-bottom: 10px;
    display: flex;
    gap: 10px;
    align-items: flex-start;
    line-height: 1.5;
}

.guide-steps li::before {
    content: "";
    width: 6px;
    height: 6px;
    background: var(--tesla-red);
    border-radius: 50%;
    margin-top: 6px;
    flex-shrink: 0;
}

.toggle-icon {
    font-size: 12px;
    transition: var(--transition);
    opacity: 0.5;
}

.toggle-icon.collapsed {
    transform: rotate(-180deg);
}

/* Upload Dropzone */
.upload-zone {
    position: relative;
    background: var(--card-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 2px dashed var(--glass-border);
    border-radius: 24px;
    padding: 60px 20px;
    text-align: center;
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 16px;
}

.upload-zone:hover {
    border-color: var(--tesla-red);
    background: var(--card-hover);
}

.upload-zone.active {
    border-color: var(--tesla-red);
    background: rgba(232, 33, 39, 0.1);
}

.upload-icon {
    width: 64px;
    height: 64px;
    background: rgba(232, 33, 39, 0.1);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 8px;
    transition: var(--transition);
}

.upload-zone:hover .upload-icon {
    background: var(--tesla-red);
}

.upload-icon svg {
    width: 32px;
    height: 32px;
    fill: var(--tesla-red);
    transition: var(--transition);
}

.upload-zone:hover .upload-icon svg {
    fill: white;
}

.upload-zone p {
    font-size: 16px;
    margin: 0;
    color: var(--text-secondary);
}

.inputer {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    opacity: 0;
    cursor: pointer;
    z-index: 10;
}

/* Video Viewer & WebGL Canvas */
.viewer {
    width: 100%;
    background: #000;
    overflow: hidden;
    border: 1px solid var(--glass-border);
    position: relative;
    box-shadow: 0 20px 80px rgba(0, 0, 0, 0.6);
    display: none;
    animation: fadeIn 0.8s cubic-bezier(0.16, 1, 0.3, 1);
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.canvas-container {
    width: 100%;
    position: relative;
    background: #000;
    cursor: pointer;
}

canvas {
    width: 100%;
    display: block;
}

/* Controls & Overlay */
.controls-overlay {
    padding: 16px;
    background: linear-gradient(0deg, var(--glass-bg) 0%, transparent 100%);
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.status-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    font-size: 12px;
    height: 26px;
    padding: 0 14px;
    background: rgba(255, 255, 255, 0.05);
    backdrop-filter: blur(10px);
    border-radius: 20px;
    color: var(--text-secondary);
    line-height: 1;
    font-weight: 500;
    border: 1px solid var(--glass-border);
}

.reselect-btn {
    background: rgba(232, 33, 39, 0.15);
    border: 1px solid rgba(232, 33, 39, 0.3);
    color: var(--tesla-red);
    font-size: 12px;
    height: 26px;
    padding: 0 14px;
    border-radius: 20px;
    cursor: pointer;
    transition: var(--transition);
    display: none;
    align-items: center;
    justify-content: center;
    line-height: 1;
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    font-weight: 600;
    letter-spacing: 0.5px;
}

.reselect-btn:hover {
    background: var(--tesla-red);
    color: white;
    border-color: var(--tesla-red);
    box-shadow: 0 4px 15px rgba(232, 33, 39, 0.4);
}

.status-badge.recording {
    background: rgba(232, 33, 39, 0.1);
    color: var(--tesla-red);
    border-color: rgba(232, 33, 39, 0.2);
}

.status-badge .dot {
    display: none;
}

.status-badge.recording .dot {
    display: inline-block;
    width: 8px;
    height: 8px;
    background: var(--tesla-red);
    border-radius: 50%;
    animation: pulse 1.5s infinite;
    box-shadow: 0 0 8px var(--tesla-red);
}

@keyframes pulse {
    0% {
        opacity: 1;
        transform: scale(1);
    }
    50% {
        opacity: 0.5;
        transform: scale(1.2);
    }
    100% {
        opacity: 1;
        transform: scale(1);
    }
}

.timeline-container {
    width: 100%;
    display: flex;
    align-items: center;
    gap: 16px;
}

.icon-btn {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--glass-border);
    color: var(--text-primary);
    cursor: pointer;
    padding: 0;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    transition: var(--transition);
}

.icon-btn:disabled {
    opacity: 0.2;
    cursor: not-allowed;
}

.slider-container {
    flex: 1;
    position: relative;
    height: 6px;
    display: flex;
    align-items: center;
}

input[type="range"] {
    -webkit-appearance: none;
    appearance: none;
    width: 100%;
    height: 4px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 2px;
    outline: none;
}

input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 16px;
    height: 16px;
    background: #fff;
    border-radius: 50%;
    cursor: pointer;
    transition: var(--transition);
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.5);
}

input[type="range"]::-webkit-slider-thumb:hover {
    background: var(--tesla-red);
    transform: scale(1.2);
    box-shadow: 0 0 15px var(--tesla-red);
}

.btn-group {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
}

.btn {
    height: 52px;
    border: none;
    border-radius: 14px;
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    text-transform: uppercase;
    letter-spacing: 2px;
}

.btn-primary {
    background: var(--tesla-red);
    color: white;
    box-shadow: 0 4px 15px rgba(232, 33, 39, 0.2);
}

.btn-primary:hover:not(:disabled) {
    background: #ff2a31;
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(232, 33, 39, 0.4);
}

.btn-secondary {
    background: rgba(255, 255, 255, 0.05);
    color: white;
    border: 1px solid var(--glass-border);
    backdrop-filter: blur(10px);
}

.btn-secondary:hover:not(:disabled) {
    background: rgba(255, 255, 255, 0.1);
    transform: translateY(-2px);
    border-color: rgba(255, 255, 255, 0.2);
}

.btn:disabled {
    opacity: 0.2;
    cursor: not-allowed;
    transform: none !important;
}

@media (max-width: 600px) {
    .app-header {
        padding: 30px 20px;
    }

    .app-header h1 {
        font-size: 20px;
        letter-spacing: 4px;
    }

    .btn-group {
        grid-template-columns: 1fr;
    }
}

/* Language Segmented Toggle */
.lang-toggle-wrap {
    width: 100%;
    display: flex;
    justify-content: center;
    padding: 10px 0 15px;
    position: relative;
    z-index: 5;
    margin-top: -10px;
}

.lang-switcher {
    display: inline-flex;
    align-items: center;
    position: relative;
    background: rgba(255, 255, 255, 0.04);
    border: 1px solid var(--glass-border);
    border-radius: 22px;
    padding: 3px;
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
}

.lang-indicator {
    position: absolute;
    top: 3px;
    left: 0;
    height: calc(100% - 6px);
    border-radius: 18px;
    background: rgba(255, 255, 255, 0.13);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    box-shadow: 0 1px 10px rgba(0, 0, 0, 0.4),
        inset 0 1px 0 rgba(255, 255, 255, 0.15);
    border: 1px solid rgba(255, 255, 255, 0.15);
    pointer-events: none;
    transition: transform 0.38s cubic-bezier(0.16, 1, 0.3, 1),
        width 0.38s cubic-bezier(0.16, 1, 0.3, 1);
    will-change: transform, width;
}

.lang-option {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 6px 18px;
    border-radius: 18px;
    font-size: 13px;
    font-weight: 500;
    letter-spacing: 0.5px;
    cursor: pointer;
    color: var(--text-secondary);
    border: none;
    background: transparent;
    transition: color 0.38s cubic-bezier(0.16, 1, 0.3, 1);
    position: relative;
    z-index: 1;
    user-select: none;
    -webkit-user-select: none;
}

.lang-option:hover {
    color: rgba(255, 255, 255, 0.75);
}

.lang-option.active {
    color: var(--text-primary);
}