/* Import Google Font */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;600;700;800&display=swap');

/* CSS Variables */
:root {
    --primary-bg: #000000;
    --secondary-bg: #1a1a1a;
    --text-primary: #FFFFFF;
    --text-secondary: #999999;
    --accent-color: #FFFFFF;
    --border-color: #333333;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Reset & Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: var(--primary-bg);
    color: var(--text-primary);
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* Page Management */
.page {
    display: none;
    min-height: 100vh;
    opacity: 0;
    transition: opacity 0.4s ease;
}

.page.active {
    display: flex;
    opacity: 1;
    animation: fadeIn 0.4s ease;
}

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

/* Container */
.container {
    max-width: 600px;
    width: 100%;
    margin: 0 auto;
    padding: 40px 20px;
}

/* Home Page Styles */
#homePage {
    align-items: center;
    justify-content: center;
}

.app-title {
    font-size: clamp(2rem, 8vw, 3.5rem);
    font-weight: 800;
    text-align: center;
    letter-spacing: 2px;
    margin-bottom: 10px;
    background: linear-gradient(135deg, #FFFFFF 0%, #CCCCCC 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    animation: glow 2s ease-in-out infinite alternate;
}

@keyframes glow {
    from {
        filter: drop-shadow(0 0 10px rgba(255, 255, 255, 0.3));
    }
    to {
        filter: drop-shadow(0 0 20px rgba(255, 255, 255, 0.6));
    }
}

.subtitle {
    text-align: center;
    color: var(--text-secondary);
    font-size: 1rem;
    margin-bottom: 50px;
    font-weight: 400;
}

/* Input Section */
.input-section {
    margin-bottom: 30px;
    position: relative;
}

#messageInput {
    width: 100%;
    padding: 20px;
    background: var(--secondary-bg);
    border: 2px solid var(--border-color);
    border-radius: 12px;
    color: var(--text-primary);
    font-size: 1.1rem;
    font-family: 'Inter', sans-serif;
    resize: none;
    transition: var(--transition);
    outline: none;
}

#messageInput:focus {
    border-color: var(--accent-color);
    box-shadow: 0 0 0 3px rgba(255, 255, 255, 0.1);
}

#messageInput::placeholder {
    color: #555555;
}

.char-count {
    text-align: right;
    margin-top: 8px;
    font-size: 0.85rem;
    color: var(--text-secondary);
}

/* Buttons */
.button-group {
    display: flex;
    gap: 15px;
    flex-direction: column;
}

.btn {
    padding: 18px 32px;
    font-size: 1.1rem;
    font-weight: 700;
    border: none;
    border-radius: 12px;
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    letter-spacing: 1px;
    position: relative;
    overflow: hidden;
}

.btn::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.2);
    transform: translate(-50%, -50%);
    transition: width 0.6s, height 0.6s;
}

.btn:hover::before {
    width: 300px;
    height: 300px;
}

.btn-icon {
    font-size: 1.2rem;
}

.btn-primary {
    background: #FFFFFF;
    color: #000000;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 30px rgba(255, 255, 255, 0.3);
}

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

.btn-secondary {
    background: transparent;
    color: #FFFFFF;
    border: 2px solid #FFFFFF;
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.1);
    transform: translateY(-2px);
}

.btn-back {
    background: transparent;
    border: none;
    color: var(--text-primary);
    font-size: 1rem;
    cursor: pointer;
    padding: 10px;
    transition: var(--transition);
    display: flex;
    align-items: center;
}

.btn-back:hover {
    color: var(--accent-color);
    transform: translateX(-5px);
}

/* Settings Page */
#settingsPage {
    padding-top: 20px;
}

.settings-header {
    display: flex;
    align-items: center;
    margin-bottom: 40px;
    position: relative;
}

.settings-header h2 {
    flex: 1;
    text-align: center;
    font-size: 2rem;
    font-weight: 700;
}

.settings-content {
    display: flex;
    flex-direction: column;
    gap: 35px;
}

.setting-group {
    background: var(--secondary-bg);
    padding: 25px;
    border-radius: 12px;
    border: 1px solid var(--border-color);
    transition: var(--transition);
}

.setting-group:hover {
    border-color: #555555;
}

.setting-group label {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 15px;
    font-weight: 600;
    font-size: 1rem;
}

.setting-value {
    color: var(--accent-color);
    font-weight: 700;
}

/* Sliders */
.slider {
    width: 100%;
    height: 6px;
    border-radius: 5px;
    background: #333333;
    outline: none;
    -webkit-appearance: none;
    margin: 10px 0;
}

.slider::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: #FFFFFF;
    cursor: pointer;
    transition: var(--transition);
}

.slider::-webkit-slider-thumb:hover {
    transform: scale(1.2);
    box-shadow: 0 0 10px rgba(255, 255, 255, 0.5);
}

.slider::-moz-range-thumb {
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: #FFFFFF;
    cursor: pointer;
    border: none;
    transition: var(--transition);
}

.slider::-moz-range-thumb:hover {
    transform: scale(1.2);
    box-shadow: 0 0 10px rgba(255, 255, 255, 0.5);
}

.slider-labels {
    display: flex;
    justify-content: space-between;
    font-size: 0.85rem;
    color: var(--text-secondary);
    margin-top: 5px;
}

/* Color Grid */
.color-grid {
    display: grid;
    grid-template-columns: repeat(6, 1fr);
    gap: 12px;
    margin-top: 15px;
}

.color-btn,
.bg-color-btn {
    width: 100%;
    aspect-ratio: 1;
    border-radius: 8px;
    border: 2px solid transparent;
    cursor: pointer;
    transition: var(--transition);
    position: relative;
}

.color-btn:hover,
.bg-color-btn:hover {
    transform: scale(1.1);
}

.color-btn.active,
.bg-color-btn.active {
    border-color: #FFFFFF;
    box-shadow: 0 0 15px rgba(255, 255, 255, 0.5);
}

.color-btn.active::after,
.bg-color-btn.active::after {
    content: '✓';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    color: #FFFFFF;
    font-size: 1.2rem;
    font-weight: bold;
    text-shadow: 0 0 5px rgba(0, 0, 0, 0.5);
}

.full-width {
    width: 100%;
}

/* Display Page */
.display-page {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: #000000;
    z-index: 1000;
    align-items: center;
    justify-content: center;
}

.close-btn {
    position: fixed;
    top: 20px;
    right: 20px;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.1);
    border: 2px solid rgba(255, 255, 255, 0.3);
    color: #FFFFFF;
    font-size: 1.5rem;
    cursor: pointer;
    transition: var(--transition);
    z-index: 1001;
    display: flex;
    align-items: center;
    justify-content: center;
    backdrop-filter: blur(10px);
}

.close-btn:hover {
    background: rgba(255, 255, 255, 0.2);
    transform: rotate(90deg);
}

.scroll-container {
    width: 100%;
    overflow: hidden;
    position: relative;
}

.scroll-text {
    display: inline-block;
    white-space: nowrap;
    font-weight: 800;
    font-size: 4rem;
    letter-spacing: 3px;
    animation: scroll 10s linear infinite;
    padding: 0 100vw;
}

@keyframes scroll {
    from {
        transform: translateX(100%);
    }
    to {
        transform: translateX(-100%);
    }
}

.timer-display {
    position: fixed;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%);
    background: rgba(255, 255, 255, 0.1);
    padding: 10px 25px;
    border-radius: 25px;
    font-size: 1.2rem;
    font-weight: 600;
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 30px 15px;
    }

    .app-title {
        font-size: 2.5rem;
    }

    .scroll-text {
        font-size: 2.5rem;
    }

    .color-grid {
        grid-template-columns: repeat(3, 1fr);
    }

    .button-group {
        gap: 12px;
    }
}

@media (max-width: 480px) {
    .scroll-text {
        font-size: 2rem;
    }

    .close-btn {
        width: 40px;
        height: 40px;
        font-size: 1.2rem;
    }
}