:root {
    --primary-color: #4361ee;
    --primary-hover: #3a56d4;
    --secondary-color: #3f37c9;
    --success-color: #4cc9f0;
    --text-color: rgba(255, 255, 255, 0.9);
    /* 浅色文字 */
    --text-shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
    /* 深色阴影 */
    --light-gray: rgba(255, 255, 255, 0.1);
    --medium-gray: rgba(255, 255, 255, 0.15);
    --dark-gray: rgba(255, 255, 255, 0.7);
    --white: rgba(255, 255, 255, 0.2);
    /* 低透明度白 */
    --glass-bg: rgba(255, 255, 255, 0.1);
    /* 毛玻璃背景 */
    --shadow: 0 8px 32px rgba(0, 0, 0, 0.2);
    /* 增强阴影深度 */
    --border-radius: 16px;
    /* 增加圆角增强液态感 */
}

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

body {
    line-height: 1.6;
    color: var(--text-color);
    background: linear-gradient(135deg, #60d9c3 0%, #8d98ff 100%);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    text-shadow: var(--text-shadow);
    /* 为所有文字添加阴影 */
}

/* 毛玻璃效果类 */
.glass {
    background: var(--glass-bg);
    backdrop-filter: blur(20px) saturate(100%);
    /* 高模糊 + 饱和度增强 */
    -webkit-backdrop-filter: blur(20px) saturate(100%);
    border: 1px solid rgba(255, 255, 255, 0.18);
    /* 微妙的边框增强层次 */
    box-shadow: var(--shadow),
        inset 0 1px 0 rgba(255, 255, 255, 0.1),
        /* 内发光增强液态感 */
        inset 0 -1px 0 rgba(0, 0, 0, 0.05);
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-color);
    text-decoration: none;
}

.nav-links {
    display: flex;
    gap: 1.5rem;
}

.nav-links a {
    color: var(--text-color);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s, transform 0.3s;
}

.nav-links a:hover {
    color: rgba(255, 255, 255, 1);
    transform: translateY(-1px);
}

main {
    flex: 1;
    max-width: 1200px;
    margin: 2rem auto;
    padding: 0 20px;
    width: 100%;
}

.hero {
    text-align: center;
    margin-bottom: 2rem;
}

.hero h1 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    color: var(--text-color);
    text-shadow: 0 4px 8px rgba(0, 0, 0, 0.4);
    /* 增强标题阴影 */
}

.hero p {
    font-size: 1.1rem;
    color: var(--dark-gray);
    max-width: 700px;
    margin: 0 auto 1.5rem;
    text-shadow: var(--text-shadow);
}

/* 容器应用毛玻璃效果 */
.container {
    background: var(--white);
    backdrop-filter: blur(25px) saturate(100%);
    /* 更高的模糊度 */
    -webkit-backdrop-filter: blur(25px) saturate(100%);
    border-radius: var(--border-radius);
    padding: 2rem;
    box-shadow: var(--shadow),
        inset 0 1px 1px rgba(255, 255, 255, 0.1),
        inset 0 -1px 1px rgba(0, 0, 0, 0.05);
    margin-bottom: 2rem;
    border: 1px solid rgba(255, 255, 255, 0.2);
    transition: all 0.3s ease;
}

.container:hover {
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.25),
        inset 0 1px 1px rgba(255, 255, 255, 0.15);
}

.upload-area {
    border: 2px dashed var(--medium-gray);
    border-radius: var(--border-radius);
    padding: 3rem 2rem;
    text-align: center;
    margin-bottom: 2rem;
    transition: all 0.3s;
    cursor: pointer;
    position: relative;
    background: rgba(255, 255, 255, 0.08);
    backdrop-filter: blur(15px);
    -webkit-backdrop-filter: blur(15px);
}

.upload-area:hover {
    border-color: rgba(255, 255, 255, 0.4);
    background: rgba(255, 255, 255, 0.12);
    transform: translateY(-2px);
}

.upload-area.active {
    border-color: var(--primary-color);
    background: rgba(67, 97, 238, 0.15);
}

.upload-icon {
    font-size: 3rem;
    color: rgba(255, 255, 255, 0.9);
    margin-bottom: 1rem;
    filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.3));
}

.upload-text {
    font-size: 1.2rem;
    margin-bottom: 0.5rem;
    color: var(--text-color);
    text-shadow: var(--text-shadow);
}

.upload-hint {
    color: var(--dark-gray);
    font-size: 0.9rem;
    text-shadow: var(--text-shadow);
}

.controls {
    display: flex;
    flex-wrap: wrap;
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.control-group {
    flex: 1;
    min-width: 250px;
}

.control-label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: var(--text-color);
    text-shadow: var(--text-shadow);
}

.slider-container {
    display: flex;
    align-items: center;
    gap: 1rem;
}

input[type="range"] {
    flex: 1;
    -webkit-appearance: none;
    height: 8px;
    background: var(--medium-gray);
    border-radius: 10px;
    outline: none;
    background: rgba(255, 255, 255, 0.15);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
}

input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    width: 24px;
    height: 24px;
    background: rgba(255, 255, 255, 0.95);
    border-radius: 50%;
    cursor: pointer;
    transition: all 0.2s;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3),
        inset 0 1px 1px rgba(255, 255, 255, 0.8);
    border: 2px solid rgba(255, 255, 255, 0.3);
}

input[type="range"]::-webkit-slider-thumb:hover {
    transform: scale(1.15);
    background: rgba(255, 255, 255, 1);
}

.value-display {
    min-width: 40px;
    text-align: center;
    font-weight: 600;
    color: var(--text-color);
    text-shadow: var(--text-shadow);
}

.preview-container {
    position: relative;
    margin: 2rem 0;
    display: flex;
    justify-content: center;
    min-height: 200px;
}

#imagePreview {
    max-width: 100%;
    max-height: 500px;
    display: none;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    border: 1px solid rgba(255, 255, 255, 0.2);
}

#gridOverlay {
    position: absolute;
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    pointer-events: none;
    display: none;
}

.result-container {
    margin-top: 2rem;
    background: var(--light-gray);
    padding: 1.5rem;
    border-radius: var(--border-radius);
    border: 1px solid rgba(255, 255, 255, 0.15);
    position: relative;
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
}

#emojiResult {
    white-space: pre;
    line-height: 1;
    overflow-x: auto;
    max-height: 500px;
    overflow-y: auto;
    background: rgba(255, 255, 255, 0.08);
    padding: 1rem;
    border-radius: calc(var(--border-radius) - 4px);
    border: 1px solid rgba(255, 255, 255, 0.1);
    color: var(--text-color);
    text-shadow: var(--text-shadow);
    font-family: 'Courier New', monospace;
}

.button-group {
    display: flex;
    gap: 1rem;
    margin-top: 1.5rem;
    flex-wrap: wrap;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    border-radius: 50px;
    /* 胶囊按钮增强液态感 */
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s ease;
    border: none;
    font-size: 1rem;
    text-shadow: var(--text-shadow);
    background: rgba(255, 255, 255, 0.15);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    color: var(--text-color);
    position: relative;
    overflow: hidden;
}

.btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
    transition: left 0.6s;
}

.btn:hover::before {
    left: 100%;
}

.btn-primary {
    background: linear-gradient(135deg, rgba(67, 97, 238, 0.9), rgba(63, 55, 201, 0.9));
    color: white;
    border: 1px solid rgba(255, 255, 255, 0.3);
}

.btn-primary:hover {
    transform: translateY(-3px) scale(1.02);
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.25);
    background: linear-gradient(135deg, rgba(67, 97, 238, 1), rgba(63, 55, 201, 1));
}

.btn-secondary {
    background: rgba(255, 255, 255, 0.15);
    color: var(--text-color);
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.25);
    transform: translateY(-3px) scale(1.02);
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.2);
}

.btn-success {
    background: linear-gradient(135deg, rgba(76, 201, 240, 0.9), rgba(64, 180, 220, 0.9));
    color: white;
    border: 1px solid rgba(255, 255, 255, 0.3);
}

.btn-success:hover {
    background: linear-gradient(135deg, rgba(76, 201, 240, 1), rgba(64, 180, 220, 1));
    transform: translateY(-3px) scale(1.02);
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.25);
}

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

.copy-btn {
    position: absolute;
    top: 1rem;
    right: 1rem;
    padding: 0.5rem 1rem;
    font-size: 0.9rem;
}

.emoji-palette {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin: 1.5rem 0;
    justify-content: center;
    align-items: center;
    background: rgba(255, 255, 255, 0.08);
    padding: 1rem;
    border-radius: var(--border-radius);
    backdrop-filter: blur(15px);
    -webkit-backdrop-filter: blur(15px);
    border: 1px solid rgba(255, 255, 255, 0.15);
}

.emoji-palette span {
    font-size: 1.5rem;
    line-height: 1;
    filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.3));
    transition: transform 0.3s;
}

.emoji-palette span:hover {
    transform: scale(1.2);
}

.emoji-palette-title {
    width: 100%;
    text-align: center;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: var(--dark-gray);
    text-shadow: var(--text-shadow);
}

footer {
    background: rgba(255, 255, 255, 0.1);
    padding: 1.5rem 0;
    text-align: center;
    box-shadow: 0 -4px 20px rgba(0, 0, 0, 0.15);
    margin-top: auto;
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-top: 1px solid rgba(255, 255, 255, 0.15);
}

.footer-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.footer-links {
    display: flex;
    justify-content: center;
    gap: 1.5rem;
    margin-bottom: 1rem;
    flex-wrap: wrap;
}

.footer-links a {
    color: var(--dark-gray);
    text-decoration: none;
    transition: color 0.3s, transform 0.3s;
    text-shadow: var(--text-shadow);
}

.footer-links a:hover {
    color: rgba(255, 255, 255, 1);
    transform: translateY(-2px);
}

.copyright {
    color: var(--dark-gray);
    font-size: 0.9rem;
    text-shadow: var(--text-shadow);
}

.file-input {
    display: none;
}

.drag-drop-hint {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(67, 97, 238, 0.25);
    border-radius: var(--border-radius);
    opacity: 0;
    transition: opacity 0.3s;
    pointer-events: none;
    z-index: 10;
    backdrop-filter: blur(15px);
    -webkit-backdrop-filter: blur(15px);
}

.drag-drop-hint.active {
    opacity: 1;
}

.drag-drop-text {
    background: rgba(67, 97, 238, 0.9);
    color: white;
    padding: 1rem 2rem;
    border-radius: var(--border-radius);
    font-weight: 500;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
}

@media (max-width: 768px) {
    .hero h1 {
        font-size: 2rem;
    }

    .controls {
        flex-direction: column;
        gap: 1rem;
    }

    .control-group {
        width: 100%;
    }

    .button-group {
        flex-direction: column;
    }

    .btn {
        width: 100%;
    }

    .container {
        padding: 1.5rem;
        border-radius: 12px;
    }
}