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

:root {
    --primary-color: #fc1547;
    --secondary-color: #0c0c0c;
    --accent-color: #ff6b9d;
    --bg-light: #f8f9fa;
    --bg-dark: #1a1a1a;
    --text-dark: #222;
    --text-light: #666;
    --border-color: #e0e0e0;
    --success-color: #4caf50;
    --shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.15);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', 'Cantarell', sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: var(--text-dark);
    line-height: 1.6;
    min-height: 100vh;
}

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

/* 头部 */
.header {
    text-align: center;
    color: white;
    margin-bottom: 40px;
    animation: slideDown 0.6s ease-out;
}

.header h1 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 10px;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
}

.header .subtitle {
    font-size: 1.1rem;
    opacity: 0.95;
    font-weight: 300;
}

/* 主内容 */
.main-content {
    background: white;
    border-radius: 16px;
    padding: 40px;
    box-shadow: var(--shadow-lg);
    margin-bottom: 30px;
    animation: fadeIn 0.6s ease-out 0.2s both;
}

/* 音量提示（外接解码设备） */
.volume-notice {
    display: flex;
    align-items: flex-start;
    gap: 14px;
    padding: 16px 18px;
    margin: -8px 0 28px;
    border-radius: 12px;
    border: 2px solid rgba(252, 21, 71, 0.35);
    background: linear-gradient(135deg, #fff5f7 0%, #fff9fb 100%);
    box-shadow: 0 2px 12px rgba(252, 21, 71, 0.12);
}

.volume-notice-icon {
    flex-shrink: 0;
    font-size: 1.75rem;
    line-height: 1.2;
}

.volume-notice-text {
    display: flex;
    flex-direction: column;
    gap: 6px;
    font-size: 0.95rem;
    color: var(--text-dark);
    line-height: 1.55;
}

.volume-notice-text strong:first-child {
    font-size: 1.05rem;
    color: #c41e3a;
}

.volume-notice-text span {
    color: var(--text-light);
}

.volume-notice-text strong:not(:first-child) {
    color: var(--text-dark);
    font-weight: 600;
}

@media (max-width: 768px) {
    .volume-notice {
        margin-bottom: 22px;
        padding: 14px 16px;
    }
}

/* 转换器包装 */
.converter-wrapper {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 30px;
    margin-bottom: 40px;
}

@media (max-width: 768px) {
    .converter-wrapper {
        grid-template-columns: 1fr;
        gap: 20px;
    }
}

/* 输入区域 */
.input-section,
.control-section {
    display: flex;
    flex-direction: column;
}

/* 表单组 */
.form-group {
    margin-bottom: 20px;
    display: flex;
    flex-direction: column;
}

.form-group label {
    font-weight: 600;
    margin-bottom: 8px;
    color: var(--text-dark);
    font-size: 0.95rem;
}

.form-group textarea,
.form-group select,
.form-group input {
    padding: 12px 14px;
    border: 2px solid var(--border-color);
    border-radius: 8px;
    font-size: 1rem;
    font-family: inherit;
    transition: all 0.3s ease;
    background: white;
}

.form-group textarea:focus,
.form-group select:focus,
.form-group input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(252, 21, 71, 0.1);
}

.form-group textarea {
    resize: vertical;
    min-height: 120px;
    font-family: 'Courier New', monospace;
}

/* 按钮组 */
.button-group {
    display: flex;
    gap: 10px;
    margin-top: 10px;
}

.button-group .btn {
    flex: 1;
}

/* 按钮样式 */
.btn {
    padding: 12px 20px;
    border: none;
    border-radius: 8px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    white-space: nowrap;
}

.btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    color: white;
    box-shadow: 0 4px 12px rgba(252, 21, 71, 0.3);
}

.btn-primary:hover:not(:disabled) {
    transform: translateY(-2px);
    box-shadow: 0 6px 16px rgba(252, 21, 71, 0.4);
}

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

.btn-secondary {
    background: var(--bg-light);
    color: var(--text-dark);
    border: 2px solid var(--border-color);
}

.btn-secondary:hover:not(:disabled) {
    background: var(--border-color);
    border-color: var(--text-dark);
}

/* 操作按钮 */
.action-buttons {
    display: grid;
    grid-template-columns: 1fr 1fr 1fr;
    gap: 10px;
    margin-top: auto;
    padding-top: 20px;
}

@media (max-width: 768px) {
    .action-buttons {
        grid-template-columns: 1fr;
    }
}

/* 摩尔斯电码显示 */
.morse-display {
    background: var(--bg-light);
    padding: 25px;
    border-radius: 12px;
    margin-bottom: 30px;
    border-left: 4px solid var(--primary-color);
}

.morse-display h3 {
    margin-bottom: 15px;
    color: var(--text-dark);
    font-size: 1.1rem;
}

.morse-output {
    font-family: 'Courier New', monospace;
    font-size: 1.2rem;
    letter-spacing: 2px;
    word-break: break-all;
    min-height: 60px;
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    align-items: center;
    color: var(--primary-color);
    font-weight: 600;
}

.morse-char {
    background: white;
    padding: 8px 12px;
    border-radius: 6px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
    transition: all 0.2s ease;
}

.morse-char:hover {
    transform: scale(1.05);
    box-shadow: 0 4px 8px rgba(252, 21, 71, 0.2);
}

.word-gap {
    color: var(--text-light);
    font-weight: 300;
    margin: 0 4px;
}

/* 信息区域 */
.info-section {
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.1), rgba(118, 75, 162, 0.1));
    padding: 30px;
    border-radius: 12px;
    border-left: 4px solid var(--primary-color);
}

.info-section h2 {
    color: var(--text-dark);
    margin-bottom: 15px;
    font-size: 1.3rem;
}

.info-section p {
    color: var(--text-light);
    margin-bottom: 12px;
    line-height: 1.8;
}

.info-section p:last-child {
    margin-bottom: 0;
}

/* 页脚 */
.footer {
    text-align: center;
    color: white;
    padding: 20px;
    opacity: 0.9;
    font-size: 0.95rem;
}

/* 动画 */
@keyframes slideDown {
    from {
        opacity: 0;
        transform: translateY(-30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

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

/* 响应式设计 */
@media (max-width: 768px) {
    .header h1 {
        font-size: 2rem;
    }

    .main-content {
        padding: 20px;
    }

    .converter-wrapper {
        gap: 20px;
    }

    .form-group textarea {
        min-height: 100px;
    }

    .morse-output {
        font-size: 1rem;
    }

    .info-section {
        padding: 20px;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 10px;
    }

    .header h1 {
        font-size: 1.5rem;
    }

    .main-content {
        padding: 15px;
        border-radius: 12px;
    }

    .header .subtitle {
        font-size: 1rem;
    }

    .form-group textarea {
        min-height: 80px;
        font-size: 0.95rem;
    }

    .btn {
        padding: 10px 16px;
        font-size: 0.9rem;
    }

    .action-buttons {
        grid-template-columns: 1fr;
        gap: 8px;
    }
}

/* 滚动条美化 */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-light);
}

::-webkit-scrollbar-thumb {
    background: var(--primary-color);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--accent-color);
}