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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: linear-gradient(120deg, #232526 0%, #414345 100%);
    color: #f3f3f3;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
    position: relative;
    overflow-x: hidden;
}

body::before {
    content: '';
    position: fixed;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle at 60% 40%, rgba(0, 255, 200, 0.08) 0%, transparent 60%);
    pointer-events: none;
    z-index: 0;
}

@keyframes ambient-rotate {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

.app-container {
    width: 100%;
    max-width: 900px;
    margin: 0 auto;
    position: relative;
    z-index: 1;
}

.app-header {
    text-align: center;
    margin-bottom: 50px;
}


.app-header h1 {
    font-size: 56px;
    font-weight: 800;
    letter-spacing: -2px;
    margin-bottom: 12px;
    background: linear-gradient(90deg, #00ffd0 0%, #00bfff 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-shadow: 0 2px 24px rgba(0,255,200,0.12);
}

.subtitle {
    color: #b0eaff;
    font-size: 18px;
    font-weight: 500;
    letter-spacing: 0.5px;
    text-shadow: 0 1px 8px rgba(0,255,200,0.08);
}


.display-section {
    display: flex;
    justify-content: center;
    margin-bottom: 40px;
}

.display-container {
    width: 700px;
    height: 280px;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(255, 255, 255, 0.02);
    border-radius: 20px;
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.05);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
}

.guide-line-horizontal {
    position: absolute;
    width: 500px;
    height: 1px;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
    left: 50%;
    transform: translateX(-50%);
}

.guide-line-top {
    top: 50px;
}

.guide-line-bottom {
    bottom: 50px;
}

.guide-line-vertical {
    position: absolute;
    width: 1px;
    background: linear-gradient(180deg, transparent, rgba(255, 255, 255, 0.3), transparent);
    left: 50%;
    transform: translateX(-50%);
}

.guide-line-vertical-top {
    top: 50px;
    height: 60px;
}

.guide-line-vertical-bottom {
    bottom: 50px;
    height: 60px;
}

.word-display {
    position: absolute;
    z-index: 10;
    font-family: 'SF Pro Display', -apple-system, BlinkMacSystemFont, sans-serif;
    font-size: 56px;
    line-height: 1;
    display: inline-flex;
    align-items: baseline;
    white-space: nowrap;
    user-select: none;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    letter-spacing: -1px;
    text-shadow: 0 2px 20px rgba(0, 0, 0, 0.5);
}

.word-before {
    color: #666;
    font-weight: 400;
    text-align: right;
    transition: color 0.2s ease;
}

.word-after {
    color: #666;
    font-weight: 400;
    text-align: left;
    transition: color 0.2s ease;
}

.word-orp {
    color: #FF4444;
    font-weight: 400;
    position: relative;
    display: inline-block;
    text-align: center;
    filter: none;
    transition: all 0.2s ease;
}

/* Heading word styling: keep visual weight consistent with normal words */
.word-display.heading-word {
    /* keep the same base size as normal display to avoid large jumps */
    font-size: 56px;
    font-weight: 400;
    letter-spacing: -1px;
}

.word-display.heading-word .word-before,
.word-display.heading-word .word-after {
    color: inherit;
    font-weight: 400;
    filter: none;
}

/* Keep ORP red even for heading-word so the pivot letter remains visible */
.word-display.heading-word .word-orp {
    color: #FF4444;
    font-weight: 400;
    filter: none;
}

.progress-section {
    margin-bottom: 30px;
}

.word-counter {
    text-align: center;
    color: #888;
    font-size: 15px;
    margin-bottom: 12px;
    font-weight: 500;
    letter-spacing: 0.5px;
}

.current-word {
    color: #fff;
    font-weight: 600;
}

.progress-bar-container {
    width: 100%;
    height: 4px;
    background-color: rgba(255, 255, 255, 0.05);
    border-radius: 2px;
    overflow: hidden;
    box-shadow: inset 0 1px 3px rgba(0, 0, 0, 0.3);
}

.progress-bar-fill {
    height: 100%;
    width: 0%;
    background: linear-gradient(90deg, #4CAF50 0%, #66BB6A 100%);
    border-radius: 2px;
    transition: width 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 0 10px rgba(76, 175, 80, 0.5);
}

.controls-section {
    margin-bottom: 30px;
}

.controls-container {
    background: rgba(255, 255, 255, 0.03);
    backdrop-filter: blur(20px);
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: 16px;
    padding: 28px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 24px;
    flex-wrap: wrap;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
}

.playback-controls {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}

.control-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 7px;
    padding: 11px 22px;
    border: none;
    border-radius: 6px;
    font-size: 14px;
    font-weight: 600;
    color: #fff;
    cursor: pointer;
    transition: all 0.2s ease;
    font-family: inherit;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.15);
    letter-spacing: 0.3px;
}

.control-btn:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.25);
}

.control-btn:active {
    transform: translateY(0);
}

.control-btn:disabled {
    opacity: 0.35;
    cursor: not-allowed;
    transform: none;
}

.play-btn {
    background: #10b981;
}

.play-btn:hover {
    background: #059669;
}

.pause-btn {
    background: #f59e0b;
}

.pause-btn:hover {
    background: #d97706;
}

.restart-btn {
    background: #3b82f6;
}

.restart-btn:hover {
    background: #2563eb;
}

.btn-icon {
    font-size: 16px;
    line-height: 1;
}

.speed-control {
    display: flex;
    align-items: center;
    gap: 14px;
}

.speed-label {
    font-size: 14px;
    font-weight: 600;
    color: #999;
    letter-spacing: 0.5px;
    text-transform: uppercase;
}

.speed-selector {
    padding: 11px 16px;
    background: rgba(0, 0, 0, 0.4);
    border: 1px solid rgba(255, 255, 255, 0.12);
    border-radius: 6px;
    color: #fff;
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
    font-family: inherit;
    backdrop-filter: blur(10px);
    letter-spacing: 0.3px;
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg width='12' height='8' viewBox='0 0 12 8' fill='none' xmlns='http://www.w3.org/2000/svg'%3E%3Cpath d='M1 1.5L6 6.5L11 1.5' stroke='%23999' stroke-width='2' stroke-linecap='round'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 12px center;
    padding-right: 36px;
}

.speed-selector:hover {
    background-color: rgba(0, 0, 0, 0.5);
    border-color: rgba(255, 255, 255, 0.2);
}

.speed-selector:focus {
    outline: none;
    border-color: #3b82f6;
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.15);
}

.speed-selector option {
    background: #1a1a1a;
    color: #fff;
    padding: 10px;
}

.input-section {
    background: rgba(255, 255, 255, 0.03);
    backdrop-filter: blur(20px);
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: 16px;
    padding: 28px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
}

.input-title {
    font-size: 16px;
    font-weight: 600;
    margin-bottom: 18px;
    color: #e5e5e5;
    letter-spacing: -0.3px;
}

.input-container {
    display: flex;
    flex-direction: column;
    gap: 14px;
}

.text-input {
    width: 100%;
    min-height: 140px;
    padding: 16px;
    background: rgba(0, 0, 0, 0.35);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 8px;
    color: #fff;
    font-size: 14px;
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    line-height: 1.6;
    resize: vertical;
    transition: all 0.2s ease;
    backdrop-filter: blur(10px);
}

.text-input::placeholder {
    color: #666;
}

.text-input:focus {
    outline: none;
    border-color: #3b82f6;
    background: rgba(0, 0, 0, 0.45);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.15);
}

.load-btn {
    width: 100%;
    padding: 14px;
    background: #3b82f6;
    border: none;
    border-radius: 8px;
    color: #fff;
    font-size: 15px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
    font-family: inherit;
    box-shadow: 0 2px 8px rgba(59, 130, 246, 0.25);
    letter-spacing: 0.3px;
}

.load-btn:hover {
    background: #2563eb;
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(59, 130, 246, 0.35);
}

.load-btn:active {
    transform: translateY(0);
}

.load-btn:disabled {
    opacity: 0.35;
    cursor: not-allowed;
    transform: none;
}

@media (max-width: 768px) {
    .display-container {
        width: 100%;
        max-width: 500px;
    }
    
    .guide-line-horizontal {
        width: 90%;
    }
    
    .word-display {
        font-size: 44px;
    }
    
    .controls-container {
        flex-direction: column;
        align-items: stretch;
    }
    
    .playback-controls {
        justify-content: center;
    }
    
    .speed-control {
        justify-content: center;
    }
}

@media (max-width: 480px) {
    .app-header h1 {
        font-size: 38px;
    }
    
    .word-display {
        font-size: 38px;
    }
    
    .control-btn {
        padding: 12px 20px;
        font-size: 14px;
    }
}