:root {
    --primary-color: #BAE1FF;
    --secondary-color: #FFB3BA;
    --accent-color: #f093fb;
    --success-color: #4ade80;
    --warning-color: #f59e0b;
    --error-color: #ef4444;
    --text-primary: #2c3e50;
    --text-secondary: #666;
    --bg-light: #f8f9ff;
    --bg-white: #ffffff;

    --glass-bg: linear-gradient(135deg, 
        rgba(255, 255, 255, 0.25),
        rgba(255, 255, 255, 0.15));
    --glass-border: rgba(255, 255, 255, 0.35);
    --glass-shadow: 0 8px 32px rgba(31, 38, 135, 0.25);
    --border-color: #e1e8ed;
    --shadow: 0 10px 30px rgba(0,0,0,0.1);
    --shadow-hover: 0 20px 40px rgba(0,0,0,0.15);
    --border-radius: 16px;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --content-max-width: 1200px;
}

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

button, input, textarea, select {
    font-family: inherit;
}

body {
    font-family: 'Gowun Dodum', 'Lato', sans-serif;
    background: url('../img/background.png') center center / cover no-repeat,
                linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    background-attachment: fixed;
    min-height: 100vh;
    line-height: 1.6;
    color: var(--text-primary);
    display: flex;
    flex-direction: column;
}

html[lang="ja"] body,
html[lang="ja"] * {
    font-family: 'M PLUS Rounded 1c', 'Noto Sans JP', 'Hiragino Kaku Gothic ProN', 'Hiragino Sans', 'Meiryo', sans-serif !important;
}

html[lang="ko"] body,
html[lang="ko"] * {
    font-family: 'Gowun Dodum', 'Malgun Gothic', 'Apple SD Gothic Neo', sans-serif !important;
}

.header {
    
    background: linear-gradient(135deg, 
        rgba(255, 255, 255, 0.048),
        rgba(255, 255, 255, 0.1));
    backdrop-filter: blur(15px);
    -webkit-backdrop-filter: blur(15px);

    border: 1px solid rgba(255, 255, 255, 0.35);
    border-bottom: 1px solid rgba(255, 255, 255, 0.25);

    box-shadow: 
        0 8px 32px rgba(202, 215, 255, 0.25),
        0 4px 16px rgba(255, 182, 182, 0.15),
        inset 0 1px 0 rgba(255, 255, 255, 0.6);
        
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    width: 100%;
    z-index: 100;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.header.scrolled {
    background: linear-gradient(135deg, 
        rgba(255, 255, 255, 0.12),
        rgba(255, 255, 255, 0.06));
    backdrop-filter: blur(35px);
    -webkit-backdrop-filter: blur(35px);
}

.header-content {
    max-width: var(--content-max-width);
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
    position: relative;
}

.logo {
    display: flex;
    align-items: center;
    position: relative;
    font-size: 1.4em;
    font-weight: 700;
    color: var(--text-primary);
    text-decoration: none;
    cursor: pointer;
    
}

.logo-icon {
    font-size: 1.6em;
    
    width: 1.6em;
    height: 1.6em;
    object-fit: contain;
    vertical-align: middle;
    
    position: relative;
    z-index: 1;
    
    filter: brightness(1.05) contrast(1);
}

.logo span:not(.logo-icon) {
    
    position: relative;
    z-index: 2;
    margin-left: -0.9em; 
    top: 6.5px; 
}

.nav-actions {
    display: flex;
    align-items: center;
    gap: 20px;
}

.auth-buttons {
    display: flex;
    align-items: center;
    gap: 12px;
}

.login-btn,
.settings-btn.secondary,
.settings-btn.primary {
    background: rgba(255, 255, 255);
    color: var(--text-primary);
    border: 1px solid rgba(255, 255, 255, 0.2);
    padding: 10px 20px;
    border-radius: 25px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    font-size: 14px;
    text-decoration: none;
    display: inline-block;
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    position: relative;
    overflow: hidden;
    box-shadow: #2C3E50;
}
.settings-btn.secondary{
    border: 2px solid #e0e0e0;
}
.login-btn::before,
.settings-btn.secondary::before,
.settings-btn.primary::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, 
        transparent, 
        rgba(99, 102, 241, 0.2), 
        transparent);
    transition: left 0.6s ease;
}

.login-btn:hover,
.settings-btn.secondary:hover,
.settings-btn.primary:hover {
    background: rgba(255, 255, 255, 0.15);
    border-color: rgba(203, 204, 255, 0.4);
    color: var(--text-primary);
    transform: translateY(-1px);
    box-shadow: 0 4px 15px rgba(31, 38, 135, 0.2);
}

.login-btn:hover::before,
.settings-btn.secondary:hover::before,
.settings-btn.primary:hover::before {
    left: 100%;
}

.signup-btn {
    background: linear-gradient(135deg, 
        rgba(99, 102, 241, 0.4), 
        rgba(255, 107, 107, 0.4));
    color: white;
    border: 1px solid rgba(255, 255, 255, 0.2);
    padding: 10px 24px;
    border-radius: 25px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    font-size: 14px;
    text-decoration: none;
    display: inline-block;
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    position: relative;
    overflow: hidden;
    box-shadow: 
        0 4px 15px rgba(99, 102, 241, 0.3),
        inset 0 1px 0 rgba(255, 255, 255, 0.3);
}

.signup-btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, 
        transparent, 
        rgba(255, 255, 255, 0.3), 
        transparent);
    transition: left 0.6s ease;
}

.signup-btn:hover {
    background: linear-gradient(135deg, 
        rgba(99, 102, 241, 0.9), 
        rgba(255, 107, 107, 0.9));
    transform: translateY(-1px);
    box-shadow: 
        0 6px 20px rgba(99, 102, 241, 0.4),
        inset 0 1px 0 rgba(255, 255, 255, 0.4);
}

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

.user-info {
    display: flex;
    align-items: center;
    gap: 15px;
}

.user-name {
    font-weight: 600;
}

.usage-badge {
    color: var(--text-primary-color);
    padding: 6px 14px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 500;
    border: 1px solid rgba(99, 102, 241, 0.2);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    box-shadow: 
        0 2px 8px rgba(99, 102, 241, 0.2),
        inset 0 1px 0 rgba(255, 255, 255, 0.3);
}

.usage-badge.warning {
    background: linear-gradient(135deg, 
        rgba(255, 193, 7, 0.2), 
        rgba(255, 193, 7, 0.1));
    color: var(--warning-color);
    border-color: rgba(255, 193, 7, 0.3);
    box-shadow: 
        0 2px 8px rgba(255, 193, 7, 0.2),
        inset 0 1px 0 rgba(255, 255, 255, 0.3);
}

.logout-btn {
    background: rgba(255, 255, 255, 0.1);
    color: var(--text-secondary);
    border: 1px solid rgba(255, 255, 255, 0.2);
    padding: 8px 16px;
    border-radius: 20px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    font-size: 13px;
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    position: relative;
    overflow: hidden;
}

.logout-btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, 
        transparent, 
        rgba(248, 113, 113, 0.2), 
        transparent);
    transition: left 0.6s ease;
}

.logout-btn:hover {
    background: rgba(248, 113, 113, 0.15);
    border-color: rgba(248, 113, 113, 0.4);
    color: var(--error-color);
    transform: translateY(-1px);
    box-shadow: 0 4px 15px rgba(248, 113, 113, 0.2);
}

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

.guest-banner {
    background: linear-gradient(135deg, #fef3c7 0%, #fde68a 100%);
    border-bottom: 1px solid var(--warning-color);
    padding: 12px 0;
    text-align: center;
    animation: slideDown 0.5s ease-out;
}

@keyframes slideDown {
    from { transform: translateY(-100%); opacity: 0; }
    to { transform: translateY(0); opacity: 1; }
}

.guest-banner-content {
    max-width: var(--content-max-width);
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 15px;
    flex-wrap: wrap;
}

.guest-message {
    color: #92400e;
    font-weight: 500;
    font-size: 14px;
}

.main-container {
    flex: 1;
    max-width: var(--content-max-width);
    margin: 0 auto;
    margin-top: 2%;
    padding: 60px 20px;
    width: 100%;
}

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

.form-label {
    display: block;
    margin-bottom: 8px;
    color: #333;
    font-weight: 500;
}

.form-input {
    width: 100%;
    padding: 16px 20px;
    border: 2px solid var(--border-color);
    border-radius: var(--border-radius);
    font-size: 16px;
    font-family: inherit;
    transition: var(--transition);
    background: #fafbfc;
}

.form-input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 4px rgba(102, 126, 234, 0.1);
    background: white;
}

.input-field {
    width: 100%;
    padding: 12px 16px;
    border: 2px solid var(--border-color);
    border-radius: var(--border-radius);
    font-size: 16px;
    font-family: inherit;
    transition: var(--transition);
    background: #fafbfc;
}

.input-field:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 4px rgba(102, 126, 234, 0.1);
    background: white;
}

.submit-btn {
    background: linear-gradient(135deg, rgba(99, 102, 241, 0.2), rgba(255, 107, 107, 0.2));
    color: #2C3E50;
    border: none;
    padding: 16px 40px;
    font-size: 16px;
    font-weight: 600;
    border-radius: 50px;
    cursor: pointer;
    transition: var(--transition);
    box-shadow: var(--shadow);
    width: 100%;
}

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

.submit-btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
}

.footer {
    
    background: linear-gradient(135deg, 
        rgba(255, 255, 255, 0.048),
        rgba(255, 255, 255, 0.1));
    backdrop-filter: blur(15px);

    border: 1px solid rgba(255, 255, 255, 0.35);
    border-top: 1px solid rgba(255, 255, 255, 0.25);

    box-shadow: 
        0 -8px 32px rgba(202, 215, 255, 0.25),
        0 -4px 16px rgba(255, 182, 182, 0.15),
        inset 0 -1px 0 rgba(255, 255, 255, 0.6);
    
    color: var(--text-primary);
    text-align: center;
    padding: 40px 20px;
    margin-top: auto;
    position: relative;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.footer-content {
    max-width: var(--content-max-width);
    margin: 0 auto;
    position: relative;
    z-index: 2;
}

.footer-link {
    color: var(--text-primary);
    text-decoration: none;
    transition: all 0.3s ease;
    font-size: 14px;
    position: relative;
    padding: 5px 0;
}

.footer-link::before {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    width: 0;
    height: 1px;
    background: linear-gradient(90deg, 
        var(--primary-color), 
        var(--accent-color));
    transition: all 0.3s ease;
    transform: translateX(-50%);
}

.footer-link:hover {
    color: var(--text-primary);
    text-shadow: 0 0 8px rgba(102, 126, 234, 0.6);
}

.footer-link:hover::before {
    width: 100%;
}

.footer-links {
    display: flex;
    justify-content: center;
    gap: 30px;
    margin-bottom: 20px;
    flex-wrap: wrap;
}

.footer-copyright {
    color: #95a5a6;
    font-size: 12px;
    position: relative;
    z-index: 2;
}

@keyframes footerGlow {
    0% { 
        opacity: 0.6;
        transform: scaleX(0.9);
    }
    100% { 
        opacity: 0.9;
        transform: scaleX(1.1);
    }
}

@keyframes innerGlow {
    0%, 100% { 
        opacity: 0.8;
        transform: translate(-50%, -50%) scale(1);
    }
    50% { 
        opacity: 1;
        transform: translate(-50%, -50%) scale(1.05);
    }
}

@media (max-width: 768px) {
    .footer {
        box-shadow: 
            0 -6px 24px rgba(102, 126, 234, 0.12),
            0 -12px 48px rgba(118, 75, 162, 0.08),
            0 -18px 72px rgba(240, 147, 251, 0.06);
    }

    .footer-links {
        flex-direction: column;
        gap: 15px;
    }
}

@media (max-width: 480px) {
    .footer {
        box-shadow: 
            0 -4px 16px rgba(102, 126, 234, 0.1),
            0 -8px 32px rgba(118, 75, 162, 0.06),
            0 -12px 48px rgba(240, 147, 251, 0.04);
    }

}

@media (prefers-reduced-motion: reduce) {

    .footer-link {
        transition: color 0.2s ease;
    }
    
    .footer-link::before {
        transition: width 0.2s ease;
    }
}

@media (-webkit-min-device-pixel-ratio: 2), (min-resolution: 192dpi) {
 
}

.loading-spinner {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 2px solid rgba(255,255,255,0.3);
    border-radius: 50%;
    border-top-color: white;
    animation: spin 1s linear infinite;
    margin-right: 8px;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

@media (max-width: 768px) {
    .header-content {
        padding: 0 15px;
        height: 60px;
    }

    .logo {
        font-size: 1.2em;
    }

    .auth-buttons {
        gap: 8px;
    }

    .guest-banner-content {
        flex-direction: column;
        gap: 8px;
    }

    .main-container {
        padding: 40px 15px;
    }

    .footer-links {
        flex-direction: column;
        gap: 15px;
    }

}

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

.glass-morphism {
    background: var(--glass-bg) !important;
    backdrop-filter: blur(10px) !important;
    -webkit-backdrop-filter: blur(10px) !important;
    border: 1px solid var(--glass-border) !important;
    box-shadow: var(--glass-shadow) !important;
}

.glass-morphism:hover {
    background: linear-gradient(135deg, 
        rgba(255, 255, 255, 0.30),
        rgba(255, 255, 255, 0.20)) !important;
    box-shadow: 0 12px 40px rgba(31, 38, 135, 0.35) !important;
    transform: translateY(-2px);
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.hidden {
    display: none !important;
}

.visible {
    display: block !important;
}

.text-center {
    text-align: center;
}

.mb-20 {
    margin-bottom: 20px;
}

.mt-20 {
    margin-top: 20px;
}

.opacity-50 {
    opacity: 0.5;
}

.cursor-pointer {
    cursor: pointer;
}

.cursor-not-allowed {
    cursor: not-allowed;
}

.auth-checking #authButtons,
.auth-checking #userInfo,
.auth-checking #guestBanner,
.auth-checking #guestNotice,
.auth-checking #signupPromotion,
.auth-checking #aiModelSection,
.auth-checking #poemSidebar {
    visibility: hidden !important;
    opacity: 0;
    transition: none;
}

.user-logged-in #authButtons,
.user-logged-in #guestBanner,
.user-logged-in #guestNotice,
.user-logged-in #signupPromotion {
    display: none !important;
    visibility: hidden !important;
}

body.index-page #signupPromotion,
body.main-page #signupPromotion {
    display: none !important;
    visibility: hidden !important;
}

.user-logged-in #userInfo,
.user-logged-in #aiModelSection,
.user-logged-in #poemSidebar {
    display: flex !important;
    visibility: visible !important;
    opacity: 1;
}

.user-guest #userInfo,
.user-guest #aiModelSection,
.user-guest #poemSidebar {
    display: none !important;
    visibility: hidden !important;
}

.user-guest #authButtons {
    display: flex !important;
    visibility: visible !important;
    opacity: 1;
}

body.user-guest.poem-page #guestBanner,
body.user-guest.poem-page #guestNotice,
body.user-guest.poem-page #signupPromotion {
    display: block !important;
    visibility: visible !important;
    opacity: 1;
}

.auth-complete #authButtons,
.auth-complete #userInfo,
.auth-complete #guestBanner,
.auth-complete #guestNotice,
.auth-complete #signupPromotion,
.auth-complete #aiModelSection,
.auth-complete #poemSidebar {
    transition: opacity 0.3s ease-in-out, visibility 0.3s ease-in-out;
}

.auth-complete.user-logged-in #userInfo,
.auth-complete.user-logged-in #aiModelSection,
.auth-complete.user-logged-in #poemSidebar,
.auth-complete.user-guest #authButtons,
.auth-complete.user-guest.poem-page #guestBanner,
.auth-complete.user-guest.poem-page #guestNotice,
.auth-complete.user-guest.poem-page #signupPromotion {
    animation: smoothFadeIn 0.4s ease-out;
}

@keyframes smoothFadeIn {
    from {
        opacity: 0;
        transform: translateY(-5px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.user-logged-in .poem-creator-layout {
    grid-template-columns: 1fr 300px;
}

.user-guest .poem-creator-layout {
    grid-template-columns: 1fr;
}

@media (max-width: 1024px) {
    .user-logged-in .poem-creator-layout {
        grid-template-columns: 1fr;
    }
    
    .user-logged-in #poemSidebar {
        order: -1;
    }
}

.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(8px);
    display: none;
    justify-content: center;
    align-items: center;
    z-index: 2000;
    opacity: 0;
    transition: opacity 0.2s ease-in-out;
}

.loading-overlay.show {
    display: flex;
    opacity: 1;
}

.loading-content {
    text-align: center;
    background: white;
    padding: 40px;
    border-radius: 20px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.15);
    border: 2px solid var(--primary-color);
}

.loading-spinner-large {
    width: 50px;
    height: 50px;
    border: 3px solid var(--border-color);
    border-radius: 50%;
    border-top-color: var(--primary-color);
    animation: spin 1s linear infinite;
    margin: 0 auto 20px;
}

.loading-text {
    color: var(--text-primary);
    font-size: 16px;
    font-weight: 500;
    margin-top: 15px;
}

.auth-checking #authButtons,
.auth-checking #userInfo,
.auth-checking #guestBanner,
.auth-checking #guestNotice,
.auth-checking #signupPromotion,
.auth-checking #aiModelSection,
.auth-checking #poemSidebar {
    visibility: hidden !important;
    opacity: 0;
    transition: none;
}

@media (max-width: 768px) {
    
    body {
        background-attachment: scroll; 
        background-size: cover;
        background-position: center center;
    }
}

@media (max-width: 480px) {
    
    body {
        background-size: cover;
        background-position: center top; 
    }
}

.language-toggle-btn {
    display: flex;
    align-items: center;
    padding: 8px 15px;
    margin-right: 15px;
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 8px;
    color: var(--text-primary);
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s ease;
    backdrop-filter: blur(10px);
    white-space: nowrap;
}

.language-toggle-btn:hover {
    background: rgba(255, 255, 255, 0.15);
    border-color: rgba(255, 255, 255, 0.3);
    transform: translateY(-1px);
}

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

.language-toggle-btn:focus {
    outline: 2px solid #6a5acd;
    outline-offset: 2px;
}

.language-toggle-btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.1), rgba(255, 255, 255, 0.05));
    border-radius: 8px;
    z-index: -1;
}

@media (max-width: 768px) {
    .language-toggle-btn {
        padding: 6px 12px;
        font-size: 13px;
        margin-right: 10px;
    }
}

@media (max-width: 480px) {
    .language-toggle-btn {
        padding: 6px 10px;
        font-size: 12px;
        margin-right: 8px;
    }
}