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

body {
    font-family: 'KaiTi', '楷体', 'STKaiti', serif;
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    position: relative;
    overflow: hidden;
    background: linear-gradient(135deg, #f8f6f0 0%, #e8e2d5 50%, #d5cbb7 100%);
}

/* 返回按钮 */
.back-button {
    position: fixed;
    top: 20px;
    left: 20px;
    z-index: 1000;
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 12px 20px;
    background: rgba(139, 69, 19, 0.1);
    border: 2px solid #8b4513;
    border-radius: 20px;
    color: #8b4513;
    text-decoration: none;
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(139, 69, 19, 0.2);
}

.back-button:hover {
    background: rgba(139, 69, 19, 0.2);
    box-shadow: 0 6px 20px rgba(139, 69, 19, 0.3);
    transform: translateY(-2px);
}

/* 水墨背景 */
.ink-background {
    position: fixed;
    width: 100vw;
    height: 100vh;
    top: 0;
    left: 0;
    z-index: -1;
}

.ink-wash {
    position: absolute;
    border-radius: 50%;
    background: radial-gradient(circle, rgba(0, 0, 0, 0.1) 0%, rgba(0, 0, 0, 0.05) 40%, transparent 70%);
    animation: inkSpread 8s ease-in-out infinite;
}

.wash-1 {
    width: 300px;
    height: 200px;
    top: 10%;
    left: 15%;
    animation-delay: 0s;
}

.wash-2 {
    width: 250px;
    height: 180px;
    top: 60%;
    right: 20%;
    animation-delay: 2s;
}

.wash-3 {
    width: 200px;
    height: 150px;
    bottom: 15%;
    left: 30%;
    animation-delay: 4s;
}

@keyframes inkSpread {
    0%, 100% { transform: scale(1) rotate(0deg); opacity: 0.3; }
    50% { transform: scale(1.2) rotate(5deg); opacity: 0.6; }
}

/* 墨滴效果 */
.ink-drops {
    position: absolute;
    width: 100%;
    height: 100%;
}

.ink-drop {
    position: absolute;
    color: rgba(0, 0, 0, 0.4);
    font-size: 8px;
    animation: inkDrop 6s ease-in-out infinite;
}

.drop-1 { top: 20%; left: 25%; animation-delay: 0s; }
.drop-2 { top: 40%; right: 30%; animation-delay: 1.5s; }
.drop-3 { bottom: 30%; left: 40%; animation-delay: 3s; }
.drop-4 { top: 70%; right: 15%; animation-delay: 4.5s; }

@keyframes inkDrop {
    0% { transform: scale(0); opacity: 0; }
    20% { transform: scale(1); opacity: 1; }
    100% { transform: scale(3); opacity: 0; }
}

/* 书法元素 */
.calligraphy-elements {
    position: absolute;
    width: 100%;
    height: 100%;
}

.brush-stroke {
    position: absolute;
    color: rgba(139, 69, 19, 0.3);
    font-size: 40px;
    font-weight: bold;
    animation: brushWrite 4s ease-in-out infinite;
}

.stroke-1 { top: 15%; left: 10%; animation-delay: 0s; }
.stroke-2 { top: 25%; right: 20%; animation-delay: 1s; }
.stroke-3 { bottom: 40%; left: 20%; animation-delay: 2s; }
.stroke-4 { bottom: 20%; right: 25%; animation-delay: 3s; }

@keyframes brushWrite {
    0% { opacity: 0; transform: scale(0.5) rotate(-10deg); }
    50% { opacity: 0.6; transform: scale(1) rotate(0deg); }
    100% { opacity: 0.2; transform: scale(1.1) rotate(5deg); }
}

.seal-stamp {
    position: absolute;
    top: 20%;
    right: 10%;
    color: #dc143c;
    font-size: 24px;
    background: rgba(220, 20, 60, 0.1);
    border: 2px solid #dc143c;
    border-radius: 4px;
    padding: 8px;
    animation: sealGlow 3s ease-in-out infinite;
}

@keyframes sealGlow {
    0%, 100% { box-shadow: 0 0 10px rgba(220, 20, 60, 0.3); }
    50% { box-shadow: 0 0 20px rgba(220, 20, 60, 0.6); }
}

/* 浮动汉字 */
.floating-characters {
    position: absolute;
    width: 100%;
    height: 100%;
}

.character {
    position: absolute;
    color: rgba(139, 69, 19, 0.2);
    font-size: 20px;
    animation: floatChar 10s ease-in-out infinite;
}

.char-1 { top: 30%; left: 5%; animation-delay: 0s; }
.char-2 { top: 50%; right: 5%; animation-delay: 2.5s; }
.char-3 { bottom: 35%; left: 8%; animation-delay: 5s; }
.char-4 { bottom: 15%; right: 12%; animation-delay: 7.5s; }

@keyframes floatChar {
    0%, 100% { transform: translateY(0) rotate(0deg); opacity: 0.2; }
    50% { transform: translateY(-20px) rotate(2deg); opacity: 0.5; }
}

/* 表单容器 */
.login-container {
    width: 100%;
    max-width: 400px;
    padding: 20px;
    z-index: 100;
}

.form-container.hidden {
    display: none;
}

/* 墨韵卡片 */
.ink-card {
    background: rgba(248, 246, 240, 0.95);
    border: 3px solid rgba(139, 69, 19, 0.3);
    border-radius: 15px;
    padding: 40px 30px;
    box-shadow: 
        0 10px 30px rgba(0, 0, 0, 0.1),
        inset 0 0 20px rgba(139, 69, 19, 0.05);
    backdrop-filter: blur(10px);
    position: relative;
    overflow: hidden;
}

.ink-card::before {
    content: '';
    position: absolute;
    top: -2px;
    left: -2px;
    right: -2px;
    bottom: -2px;
    background: linear-gradient(45deg, 
        rgba(139, 69, 19, 0.3) 0%, 
        rgba(218, 165, 32, 0.3) 25%, 
        rgba(139, 69, 19, 0.3) 50%, 
        rgba(218, 165, 32, 0.3) 75%, 
        rgba(139, 69, 19, 0.3) 100%);
    border-radius: 15px;
    z-index: -1;
    animation: borderFlow 4s linear infinite;
}

@keyframes borderFlow {
    0% { background-position: 0% 0%; }
    100% { background-position: 200% 200%; }
}

.card-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 10px;
}

.ink-seal {
    font-size: 24px;
    background: rgba(139, 69, 19, 0.1);
    border: 2px solid #8b4513;
    border-radius: 50%;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    animation: sealRotate 6s ease-in-out infinite;
}

.ink-seal.register-seal {
    background: rgba(34, 139, 34, 0.1);
    border-color: #228b22;
    color: #228b22;
}

.ink-seal.reset-seal {
    background: rgba(220, 20, 60, 0.1);
    border-color: #dc143c;
    color: #dc143c;
}

@keyframes sealRotate {
    0%, 100% { transform: rotate(0deg); }
    50% { transform: rotate(5deg); }
}

.decorative-lines {
    display: flex;
    flex-direction: column;
    gap: 3px;
}

.line-ornament {
    color: rgba(139, 69, 19, 0.5);
    font-size: 16px;
    animation: ornamentWave 3s ease-in-out infinite;
}

@keyframes ornamentWave {
    0%, 100% { transform: scaleX(1); }
    50% { transform: scaleX(1.2); }
}

.ink-card h2 {
    color: #8b4513;
    font-size: 28px;
    font-weight: 600;
    text-align: center;
    margin: 0;
    text-shadow: 2px 2px 4px rgba(139, 69, 19, 0.2);
    font-family: 'KaiTi', '楷体', serif;
}

.subtitle {
    color: rgba(139, 69, 19, 0.7);
    text-align: center;
    margin-bottom: 30px;
    font-size: 14px;
    font-style: italic;
}

/* 表单样式 */
.form-group {
    position: relative;
    margin-bottom: 25px;
}

.form-group input {
    width: 100%;
    padding: 15px 0;
    background: transparent;
    border: none;
    border-bottom: 2px solid rgba(139, 69, 19, 0.3);
    color: #333;
    font-size: 16px;
    font-family: 'KaiTi', '楷体', serif;
    outline: none;
    transition: all 0.3s ease;
}

.form-group input:focus {
    border-bottom-color: #8b4513;
    box-shadow: 0 2px 10px rgba(139, 69, 19, 0.2);
}

.form-group label {
    position: absolute;
    top: 15px;
    left: 0;
    color: rgba(139, 69, 19, 0.6);
    font-size: 16px;
    pointer-events: none;
    transition: all 0.3s ease;
    font-family: 'KaiTi', '楷体', serif;
}

.form-group input:focus + label,
.form-group input:valid + label {
    top: -10px;
    font-size: 12px;
    color: #8b4513;
}

.ink-underline {
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: linear-gradient(90deg, #8b4513, #daa520);
    transition: width 0.3s ease;
    box-shadow: 0 0 10px rgba(139, 69, 19, 0.3);
}

.form-group input:focus ~ .ink-underline {
    width: 100%;
}

/* 按钮样式 */
.login-btn {
    width: 100%;
    padding: 15px;
    background: linear-gradient(135deg, rgba(139, 69, 19, 0.1), rgba(218, 165, 32, 0.1));
    border: 2px solid #8b4513;
    border-radius: 25px;
    color: #8b4513;
    font-size: 16px;
    font-weight: 600;
    font-family: 'KaiTi', '楷体', serif;
    cursor: pointer;
    position: relative;
    overflow: hidden;
    transition: all 0.3s ease;
    margin: 20px 0;
}

.login-btn:hover {
    background: linear-gradient(135deg, rgba(139, 69, 19, 0.2), rgba(218, 165, 32, 0.2));
    box-shadow: 0 8px 25px rgba(139, 69, 19, 0.3);
    transform: translateY(-2px);
}

.ink-ripple {
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(139, 69, 19, 0.2), transparent);
    transition: left 0.6s ease;
}

.login-btn:hover .ink-ripple {
    left: 100%;
}

/* 验证码组 */
.verification-group {
    display: flex;
    align-items: flex-end;
    gap: 10px;
}

.verification-group input {
    flex: 1;
}

.verify-btn {
    padding: 12px 16px;
    background: rgba(218, 165, 32, 0.1);
    border: 1px solid #daa520;
    border-radius: 15px;
    color: #222222;
    font-size: 12px;
    cursor: pointer;
    transition: all 0.3s ease;
    font-family: 'KaiTi', '楷体', serif;
    white-space: nowrap;
    flex-shrink: 0;
}

.verify-btn:hover {
    background: rgba(218, 165, 32, 0.2);
    box-shadow: 0 4px 15px rgba(218, 165, 32, 0.3);
    transform: translateY(-2px);
}

/* 附加链接 */
.additional-links {
    text-align: center;
    margin-top: 20px;
}

.ink-link {
    color: #8b4513;
    text-decoration: none;
    font-size: 14px;
    transition: all 0.3s ease;
    display: inline-flex;
    align-items: center;
    gap: 5px;
    font-family: 'KaiTi', '楷体', serif;
    position: relative;
}

.ink-link:hover {
    color: #daa520;
    text-shadow: 0 0 10px rgba(218, 165, 32, 0.5);
}

.ink-link::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 0;
    height: 1px;
    background: #daa520;
    transition: width 0.3s ease;
}

.ink-link:hover::after {
    width: 100%;
}

.divider {
    color: rgba(139, 69, 19, 0.4);
    margin: 0 15px;
    font-size: 18px;
}

/* 响应式设计 */
@media (max-width: 480px) {
    .login-container {
        padding: 15px;
    }
    
    .ink-card {
        padding: 30px 20px;
    }
    
    .back-button {
        top: 15px;
        left: 15px;
        padding: 10px 15px;
        font-size: 12px;
    }
    
    .brush-stroke {
        font-size: 30px;
    }
    
    .character {
        font-size: 16px;
    }

    .verification-group {
        gap: 8px;
    }

    .verify-btn {
        padding: 10px 12px;
        font-size: 11px;
        min-width: 70px;
    }
}