/* 네이버 NanumSquareNeo 폰트 */
@font-face {
    font-family: "NanumSquareNeoLight";
    src: url(https://hangeul.pstatic.net/hangeul_static/webfont/NanumSquareNeo/NanumSquareNeoTTF-aLt.eot);
    src: url(https://hangeul.pstatic.net/hangeul_static/webfont/NanumSquareNeo/NanumSquareNeoTTF-aLt.eot?#iefix)
            format("embedded-opentype"),
        url(https://hangeul.pstatic.net/hangeul_static/webfont/NanumSquareNeo/NanumSquareNeoTTF-aLt.woff)
            format("woff"),
        url(https://hangeul.pstatic.net/hangeul_static/webfont/NanumSquareNeo/NanumSquareNeoTTF-aLt.ttf)
            format("truetype");
}

@font-face {
    font-family: "NanumSquareNeo";
    src: url(https://hangeul.pstatic.net/hangeul_static/webfont/NanumSquareNeo/NanumSquareNeoTTF-bRg.eot);
    src: url(https://hangeul.pstatic.net/hangeul_static/webfont/NanumSquareNeo/NanumSquareNeoTTF-bRg.eot?#iefix)
            format("embedded-opentype"),
        url(https://hangeul.pstatic.net/hangeul_static/webfont/NanumSquareNeo/NanumSquareNeoTTF-bRg.woff)
            format("woff"),
        url(https://hangeul.pstatic.net/hangeul_static/webfont/NanumSquareNeo/NanumSquareNeoTTF-bRg.ttf)
            format("truetype");
}

@font-face {
    font-family: "NanumSquareNeoBold";
    src: url(https://hangeul.pstatic.net/hangeul_static/webfont/NanumSquareNeo/NanumSquareNeoTTF-cBd.eot);
    src: url(https://hangeul.pstatic.net/hangeul_static/webfont/NanumSquareNeo/NanumSquareNeoTTF-cBd.eot?#iefix)
            format("embedded-opentype"),
        url(https://hangeul.pstatic.net/hangeul_static/webfont/NanumSquareNeo/NanumSquareNeoTTF-cBd.woff)
            format("woff"),
        url(https://hangeul.pstatic.net/hangeul_static/webfont/NanumSquareNeo/NanumSquareNeoTTF-cBd.ttf)
            format("truetype");
}

:root {
    --primary: #4e41db;
    --primary-light: #6c5ce7;
    --primary-dark: #2d3436;
    --secondary: #00b894;
    --neutral-light: #f1f2f6;
    --neutral-dark: #a4b0be;
    --white: #ffffff;
    --shadow: 0 4px 15px rgba(78, 65, 219, 0.15);
    --shadow-hover: 0 8px 25px rgba(78, 65, 219, 0.25);
}

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

body {
    font-family: "NanumSquareNeoLight", 'Noto Sans KR', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    overflow: hidden;
}

/* 배경 애니메이션 */
body::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(45deg, var(--primary) 0%, var(--primary-light) 50%, var(--secondary) 100%);
    opacity: 0.9;
    z-index: -1;
}

/* 플로팅 원형 배경 요소들 */
.floating-bg {
    position: absolute;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    animation: float 6s ease-in-out infinite;
}

.floating-bg:nth-child(1) {
    width: 100px;
    height: 100px;
    top: 10%;
    left: 10%;
    animation-delay: 0s;
}

.floating-bg:nth-child(2) {
    width: 150px;
    height: 150px;
    top: 70%;
    right: 10%;
    animation-delay: 2s;
}

.floating-bg:nth-child(3) {
    width: 80px;
    height: 80px;
    top: 50%;
    left: 80%;
    animation-delay: 4s;
}

@keyframes float {
    0%, 100% { transform: translateY(0px) rotate(0deg); }
    33% { transform: translateY(-20px) rotate(120deg); }
    66% { transform: translateY(10px) rotate(240deg); }
}

.login-container {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(20px);
    border-radius: 24px;
    box-shadow: var(--shadow);
    width: 100%;
    max-width: 420px;
    margin: 20px;
    overflow: hidden;
    position: relative;
    border: 1px solid rgba(255, 255, 255, 0.3);
}

.header-section {
    background: linear-gradient(135deg, var(--primary), var(--primary-light));
    padding: 40px 30px;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.header-section::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: repeating-linear-gradient(
        45deg,
        transparent,
        transparent 10px,
        rgba(255, 255, 255, 0.03) 10px,
        rgba(255, 255, 255, 0.03) 20px
    );
    animation: slide 20s linear infinite;
}

@keyframes slide {
    0% { transform: translate(-50%, -50%) rotate(0deg); }
    100% { transform: translate(-50%, -50%) rotate(360deg); }
}

.logo-container {
    position: relative;
    z-index: 2;
    margin-bottom: 20px;
}

.logo {
    height: 40px;
    filter: brightness(0) invert(1);
    margin-bottom: 15px;
}

.system-title {
    color: var(--white);
    font-size: 22px;
    font-family: "NanumSquareNeoBold", inherit;
    margin-bottom: 8px;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}

.system-subtitle {
    color: rgba(255, 255, 255, 0.9);
    font-size: 14px;
    font-weight: 300;
}

.form-section {
    padding: 40px 30px;
}

.welcome-text {
    text-align: center;
    margin-bottom: 30px;
}

.welcome-title {
    color: var(--primary-dark);
    font-size: 18px;
    font-family: "NanumSquareNeoBold", inherit;
    margin-bottom: 8px;
}

.welcome-subtitle {
    color: var(--neutral-dark);
    font-size: 14px;
}

.form-group {
    margin-bottom: 20px;
}

.form-label {
    display: block;
    color: var(--primary-dark);
    font-size: 14px;
    font-weight: 500;
    margin-bottom: 8px;
    font-family: "NanumSquareNeo", inherit;
}

.form-input {
    width: 100%;
    padding: 16px 20px;
    border: 2px solid var(--neutral-light);
    border-radius: 12px;
    font-size: 16px;
    font-family: inherit;
    transition: all 0.3s ease;
    background: var(--white);
    outline: none;
}

.form-input:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 4px rgba(78, 65, 219, 0.1);
    transform: translateY(-1px);
}

.form-input::placeholder {
    color: var(--neutral-dark);
}

.login-button {
    width: 100%;
    height: 50px;
    background: linear-gradient(135deg, var(--primary), var(--primary-light));
    color: var(--white);
    border: none;
    padding: 18px;
    border-radius: 12px;
    font-size: 16px;
    font-weight: 600;
    font-family: "NanumSquareNeoBold", inherit;
    cursor: pointer;
    transition: all 0.3s ease;
    margin-top: 10px;
    position: relative;
    overflow: hidden;
    box-shadow: var(--shadow);
    display: flex;
    align-items: center;
    justify-content: center;
}

.login-button::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 0.5s;
}

.login-button:hover::before {
    left: 100%;
}

.login-button:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-hover);
}

.login-button:active {
    transform: translateY(0);
}

.login-button:disabled {
    opacity: 0.7;
    cursor: not-allowed;
    transform: none;
}

.footer-links {
    text-align: center;
    margin-top: 25px;
    padding-top: 20px;
    border-top: 1px solid var(--neutral-light);
}

.footer-link {
    color: var(--neutral-dark);
    font-size: 13px;
    text-decoration: none;
    margin: 0 15px;
    transition: color 0.3s ease;
}

.footer-link:hover {
    color: var(--primary);
}

/* 로딩 상태 */
.loading {
    display: none;
    align-items: center;
    justify-content: center;
    gap: 8px;
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
}

.loading.active {
    display: flex;
}

.loading-spinner {
    width: 20px;
    height: 20px;
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-top: 2px solid white;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

.button-text {
    transition: opacity 0.3s ease;
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
}

.button-text.hidden {
    opacity: 0;
}

/* 반응형 디자인 */
@media (max-width: 480px) {
    .login-container {
        margin: 10px;
        border-radius: 16px;
    }
    
    .header-section {
        padding: 30px 20px;
    }
    
    .form-section {
        padding: 30px 20px;
    }
    
    .system-title {
        font-size: 20px;
    }
    
    .welcome-title {
        font-size: 16px;
    }
    
    .form-input {
        padding: 14px 16px;
        font-size: 15px;
    }
    
    .login-button {
        padding: 16px;
        font-size: 15px;
    }
}

/* 접근성 */
@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* 다크모드 지원 */
@media (prefers-color-scheme: dark) {
    .login-container {
        background: rgba(30, 30, 30, 0.95);
        border: 1px solid rgba(255, 255, 255, 0.1);
    }
    
    .form-input {
        background: rgba(255, 255, 255, 0.05);
        border-color: rgba(255, 255, 255, 0.1);
        color: white;
    }
    
    .form-label {
        color: rgba(255, 255, 255, 0.9);
    }
    
    .welcome-title {
        color: white;
    }
}