:root {
    --green: #6ac91d;
    --green-dark: #5ab518;
    --green-darker: #427d12;
    --green-light: #e8f7d8;
    --green-glow: rgba(106, 201, 29, 0.3);
    --red: #e74c3c;
    --red-dark: #c0392b;
    --gray: #555;
    --gray-light: #f5f5f5;
    --gray-medium: #999;
    --border: #e0e0e0;
    --radius: 12px;
    --radius-lg: 24px;
    --shadow: 0 8px 32px rgba(0,0,0,0.12);
    --shadow-sm: 0 2px 8px rgba(0,0,0,0.08);
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: linear-gradient(135deg, #f0f9e8 0%, #e8f5e0 50%, #f5f5f5 100%);
    min-height: 100vh;
    display: flex;
    align-items: flex-start;
    justify-content: center;
    padding: 24px 16px;
    color: #333;
}

/* --- App --- */

.app {
    width: 100%;
    max-width: 720px;
}

/* --- Phone Frame --- */

.phone-frame {
    background: #fff;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow);
    overflow: hidden;
}

/* --- Header --- */

.phone-header {
    background: linear-gradient(135deg, var(--green), var(--green-dark));
    color: #fff;
    padding: 20px 28px 16px;
}

.phone-header h1 {
    font-size: 1.6rem;
    font-weight: 800;
    letter-spacing: 2px;
}

.phone-header .tagline {
    font-size: 0.8rem;
    opacity: 0.85;
    margin-top: 2px;
}

/* --- Status Bar --- */

.status-bar {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 12px 28px;
    background: var(--gray-light);
    font-size: 0.85rem;
    color: var(--gray);
}

.status-dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: var(--gray-medium);
    flex-shrink: 0;
}

.status-dot.ringing {
    background: #f39c12;
    animation: pulse 1s infinite;
}

.status-dot.active {
    background: var(--green);
    animation: pulse 1.5s infinite;
}

.status-dot.playing {
    background: #3498db;
    animation: pulse 0.5s infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.3; }
}

.call-timer {
    margin-left: auto;
    font-variant-numeric: tabular-nums;
    font-weight: 600;
}

/* --- Number Input --- */

.number-section {
    padding: 20px 28px;
    display: flex;
    gap: 10px;
}

.number-section input {
    flex: 1;
    padding: 12px 16px;
    border: 2px solid var(--border);
    border-radius: var(--radius);
    font-size: 1.1rem;
    outline: none;
    transition: border-color 0.2s;
}

.number-section input:focus {
    border-color: var(--green);
}

.call-btn {
    padding: 12px 28px;
    background: linear-gradient(135deg, var(--green), var(--green-dark));
    color: #fff;
    border: none;
    border-radius: var(--radius);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    white-space: nowrap;
    transition: transform 0.1s, box-shadow 0.2s;
}

.call-btn:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 12px var(--green-glow);
}

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

.call-btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none;
    box-shadow: none;
}

.hangup-btn {
    padding: 12px 28px;
    background: linear-gradient(135deg, var(--red), var(--red-dark));
    color: #fff;
    border: none;
    border-radius: var(--radius);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    white-space: nowrap;
    transition: transform 0.1s;
}

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

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

.hidden {
    display: none !important;
}

/* --- Audio Visualizer --- */

.audio-section {
    padding: 0 28px 16px;
    text-align: center;
}

.audio-section canvas {
    width: 100%;
    height: 50px;
    border-radius: 8px;
    background: var(--gray-light);
}

.audio-label {
    font-size: 0.75rem;
    color: var(--gray-medium);
    margin-top: 4px;
}

/* --- Soundboard --- */

.soundboard-section {
    border-top: 1px solid var(--border);
    padding: 20px 28px 28px;
}

.soundboard-title {
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--gray-medium);
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 14px;
}

.phrase-tabs {
    display: flex;
    gap: 6px;
    flex-wrap: wrap;
    margin-bottom: 16px;
}

.phrase-tab {
    padding: 6px 14px;
    background: var(--gray-light);
    border: 1px solid var(--border);
    border-radius: 20px;
    font-size: 0.8rem;
    cursor: pointer;
    transition: all 0.2s;
    white-space: nowrap;
}

.phrase-tab:hover {
    background: var(--green-light);
    border-color: var(--green);
}

.phrase-tab.active {
    background: var(--green);
    color: #fff;
    border-color: var(--green);
}

/* Soundboard grid */
.phrase-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 10px;
}

.sound-btn {
    display: flex;
    flex-direction: column;
    padding: 14px 16px;
    background: var(--green-light);
    color: var(--green-darker);
    border: 2px solid transparent;
    border-radius: var(--radius);
    font-size: 0.85rem;
    text-align: left;
    cursor: pointer;
    transition: all 0.15s;
    line-height: 1.4;
    position: relative;
    overflow: hidden;
}

.sound-btn:hover:not(:disabled) {
    background: #d4f0b0;
    border-color: var(--green);
    transform: translateY(-2px);
    box-shadow: var(--shadow-sm);
}

.sound-btn:active:not(:disabled) {
    transform: translateY(0);
}

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

.sound-btn.playing {
    border-color: #3498db;
    background: #e8f4fd;
    color: #2980b9;
    animation: sound-pulse 0.8s infinite;
}

@keyframes sound-pulse {
    0%, 100% { box-shadow: 0 0 0 0 rgba(52, 152, 219, 0.3); }
    50% { box-shadow: 0 0 0 6px rgba(52, 152, 219, 0); }
}

.sound-btn .sound-label {
    font-weight: 700;
    font-size: 0.9rem;
    margin-bottom: 4px;
}

.sound-btn .sound-preview {
    font-weight: 400;
    color: var(--gray);
    font-size: 0.75rem;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.sound-btn .sound-duration {
    font-size: 0.7rem;
    color: var(--gray-medium);
    margin-top: 6px;
    font-variant-numeric: tabular-nums;
}

/* --- Footer --- */

.phone-footer {
    padding: 12px 28px;
    text-align: center;
    font-size: 0.7rem;
    color: var(--gray-medium);
    border-top: 1px solid var(--border);
}

/* --- Responsive --- */

@media (max-width: 480px) {
    body {
        padding: 0;
    }

    .app {
        max-width: 100%;
    }

    .phone-frame {
        border-radius: 0;
        min-height: 100vh;
    }

    .phrase-grid {
        grid-template-columns: 1fr;
    }
}

@media (min-width: 481px) and (max-width: 720px) {
    .phrase-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (min-width: 721px) {
    .phrase-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}