:root {
    --font-scale: 1;
    --font-family: 'Roboto', sans-serif;
    --bg-color: #0e0f10;
    --card-bg: #19191a;
    --header-bg: rgba(25, 25, 26, 0.8);
    --header-text: #ffffff;
    --input-bg: #222223;
    --input-border: #333334;
    --input-focus: #00bf63;
    --text-primary: #ffffff;
    --text-secondary: #818c99;
    --primary-btn-bg: #ffffff;
    --primary-btn-text: #000000;
    --secondary-btn-bg: #2a2b2c;
    --accent-blue: #00bf63;
    --border-radius: 12px;
    --header-height: 48px;
    --transition-speed: 0.3s;
    --search-bg: #2c2d2e;
    --search-text: #ffffff;
    --tabs-bg: #222223;
    --tabs-active-bg: #454647;
    --card-shadow: 0 20px 40px rgba(0,0,0,0.4);
    --stroke-color: %23818c99;
}

[data-theme="light"] {
    --bg-color: #f0f2f5;
    --card-bg: #ffffff;
    --header-bg: rgba(255, 255, 255, 0.8);
    --header-text: #1c1e21;
    --input-bg: #f2f3f5;
    --input-border: #dcdfe3;
    --input-focus: #00bf63;
    --text-primary: #1c1e21;
    --text-secondary: #65676b;
    --primary-btn-bg: #00bf63;
    --primary-btn-text: #ffffff;
    --secondary-btn-bg: #ebedf0;
    --accent-blue: #00bf63;
    --search-bg: #f2f3f5;
    --search-text: #1c1e21;
    --tabs-bg: #f2f3f5;
    --tabs-active-bg: #ffffff;
    --card-shadow: 0 10px 30px rgba(0,0,0,0.08);
    --stroke-color: %23dcdfe3;
}

body {
    margin: 0;
    padding: 0;
    background-color: var(--bg-color);
    color: var(--text-primary);
    font-family: var(--font-family);
    -webkit-font-smoothing: antialiased;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    overflow-x: hidden;
    transition: background-color var(--transition-speed), color var(--transition-speed);
}

.auth-card, .top-header, .input-field, .btn-primary, .btn-secondary, .qr-btn, .search-container, .auth-tabs, .auth-tab {
    transition: background-color var(--transition-speed), border-color var(--transition-speed), color var(--transition-speed), box-shadow var(--transition-speed);
}

/* Theme Toggle Button */
.theme-toggle-btn {
    background: transparent;
    border: none;
    color: var(--text-secondary);
    font-size: calc(20px * var(--font-scale));
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    border-radius: 50%;
    transition: background-color 0.2s;
}

.theme-toggle-btn:hover {
    background-color: rgba(129, 140, 153, 0.2);
    color: var(--text-primary);
}

[data-theme="light"] .theme-toggle-btn .fa-sun {
    display: none;
}

[data-theme="dark"] .theme-toggle-btn .fa-moon {
    display: none;
}

html:not([data-theme="light"]) .theme-toggle-btn .fa-moon {
    display: block;
}
html:not([data-theme="light"]) .theme-toggle-btn .fa-sun {
    display: none;
}
html[data-theme="light"] .theme-toggle-btn .fa-sun {
    display: block;
}
html[data-theme="light"] .theme-toggle-btn .fa-moon {
    display: none;
}

/* Top Bar */
.top-header {
    height: calc(var(--header-height) + env(safe-area-inset-top));
    background-color: var(--header-bg);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: env(safe-area-inset-top) 16px 0;
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 100;
}

.header-left {
    display: flex;
    align-items: center;
    gap: 12px;
    flex: 1;
}

.search-container {
    background-color: var(--search-bg);
    border-radius: 8px;
    padding: 4px 12px;
    display: flex;
    align-items: center;
    gap: 8px;
    max-width: 240px;
    width: 100%;
}

.search-container i {
    color: var(--text-secondary);
    font-size: calc(14px * var(--font-scale));
}

.search-container input {
    background: transparent;
    border: none;
    color: var(--search-text);
    font-size: calc(14px * var(--font-scale));
    outline: none;
    width: 100%;
}

.header-right {
    display: flex;
    align-items: center;
    gap: 16px;
}

.business-btn {
    background-color: var(--search-bg);
    color: var(--header-text);
    padding: 6px 16px;
    border-radius: 8px;
    font-size: calc(13px * var(--font-scale));
    font-weight: 500;
    text-decoration: none;
}

.business-btn:hover {
    background-color: var(--tabs-active-bg);
}

/* Auth Container */
.auth-container {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: calc(80px + env(safe-area-inset-top)) 20px calc(40px + env(safe-area-inset-bottom)); /* Offset for header */
    z-index: 1;
    position: relative;
}

.auth-card {
    background-color: var(--card-bg);
    width: 100%;
    max-width: 440px;
    border-radius: var(--border-radius);
    padding: 32px;
    box-shadow: var(--card-shadow);
    animation: fadeIn 0.5s ease-out;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

.logo-section {
    display: flex;
    flex-direction: column;
    align-items: center;
    margin-bottom: 24px;
}

.app-logo {
    width: 48px;
    height: 48px;
    background-color: var(--accent-blue);
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: calc(20px * var(--font-scale));
    font-weight: bold;
    color: white;
    margin-bottom: 16px;
}

.auth-card h1 {
    font-size: calc(20px * var(--font-scale));
    font-weight: 600;
    margin: 0;
    text-align: center;
}

/* Tabs */
.auth-tabs {
    display: flex;
    background-color: var(--tabs-bg);
    border-radius: 8px;
    padding: 2px;
    margin: 24px 0;
    border: 1px solid var(--input-border);
}

.auth-tab {
    flex: 1;
    text-align: center;
    padding: 8px;
    font-size: calc(14px * var(--font-scale));
    font-weight: 500;
    color: var(--text-secondary);
    cursor: pointer;
    border-radius: 6px;
}

.auth-tab.active {
    background-color: var(--tabs-active-bg);
    color: var(--text-primary);
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

[data-theme="light"] .auth-tab.active {
    background-color: var(--card-bg);
}

/* Form Elements */
.form-group {
    margin-bottom: 16px;
}

.input-field {
    width: 100%;
    background-color: var(--input-bg);
    border: 1px solid var(--input-border);
    color: var(--text-primary);
    padding: 12px 16px;
    border-radius: 8px;
    font-size: calc(16px * var(--font-scale));
    outline: none;
    box-sizing: border-box;
}

.input-field:focus {
    border-color: var(--input-focus);
}

.input-field::placeholder {
    color: var(--text-secondary);
    opacity: 0.6;
}

.checkbox-group {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: calc(14px * var(--font-scale));
    color: var(--text-secondary);
    margin-bottom: 24px;
    cursor: pointer;
}

.checkbox-group input {
    width: 18px;
    height: 18px;
    accent-color: var(--accent-blue) !important;
    cursor: pointer;
}

/* Buttons */
.btn-primary {
    width: 100%;
    background-color: var(--primary-btn-bg);
    color: var(--primary-btn-text);
    border: none;
    padding: 14px;
    border-radius: 8px;
    font-size: calc(16px * var(--font-scale));
    font-weight: 600;
    cursor: pointer;
    margin-bottom: 12px;
}

.btn-primary:hover {
    opacity: 0.9;
}

.btn-secondary {
    width: 100%;
    background-color: transparent;
    border: 1px solid var(--input-border);
    color: var(--text-primary);
    padding: 14px;
    border-radius: 8px;
    font-size: calc(16px * var(--font-scale));
    font-weight: 600;
    cursor: pointer;
}

.btn-secondary:hover {
    background-color: rgba(129, 140, 153, 0.1);
}

.divider {
    display: flex;
    align-items: center;
    text-align: center;
    color: var(--text-secondary);
    font-size: calc(12px * var(--font-scale));
    margin: 20px 0;
}

.divider::before,
.divider::after {
    content: '';
    flex: 1;
    border-bottom: 1px solid var(--input-border);
}

.divider:not(:empty)::before {
    margin-right: .5em;
}

.divider:not(:empty)::after {
    margin-left: .5em;
}

.qr-btn {
    width: 100%;
    background-color: var(--input-bg);
    border: 1px solid var(--input-border);
    color: var(--text-primary);
    padding: 12px;
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    font-size: calc(15px * var(--font-scale));
    font-weight: 500;
    cursor: pointer;
}

.qr-btn:hover {
    background-color: rgba(129, 140, 153, 0.1);
}

/* Decorative Background Lines */
.bg-lines {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 0;
    opacity: 0.2;
    pointer-events: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='100%25' height='100%25'%3E%3Cg fill='none' stroke-linecap='round'%3E%3Cpath d='M-60%2C80 Q300%2C420 220%2C780' stroke='%23818c99' stroke-width='2.5' stroke-opacity='0.2' /%3E%3Cpath d='M900%2C-60 Q1100%2C300 1320%2C520' stroke='%23818c99' stroke-width='2' stroke-opacity='0.15' /%3E%3Cpath d='M-100%2C600 Q350%2C200 600%2C-80' stroke='%23818c99' stroke-width='1.5' stroke-opacity='0.1' /%3E%3Cpath d='M1100%2C800 Q1250%2C400 980%2C-100' stroke='%23818c99' stroke-width='1.2' stroke-opacity='0.08' /%3E%3C/g%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-size: 100% 100%;
    background-position: center;
}

[data-theme="light"] .bg-lines {
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='100%25' height='100%25'%3E%3Cg fill='none' stroke-linecap='round'%3E%3Cpath d='M-60%2C80 Q300%2C420 220%2C780' stroke='%23dcdfe3' stroke-width='2.5' stroke-opacity='0.5' /%3E%3Cpath d='M900%2C-60 Q1100%2C300 1320%2C520' stroke='%23dcdfe3' stroke-width='2' stroke-opacity='0.4' /%3E%3Cpath d='M-100%2C600 Q350%2C200 600%2C-80' stroke='%23dcdfe3' stroke-width='1.5' stroke-opacity='0.3' /%3E%3Cpath d='M1100%2C800 Q1250%2C400 980%2C-100' stroke='%23dcdfe3' stroke-width='1.2' stroke-opacity='0.2' /%3E%3C/g%3E%3C/svg%3E");
}

.help-link-centered {
    margin: 40px 0;
    text-align: center;
}

.help-link-centered a {
    color: var(--text-primary);
    font-size: calc(14px * var(--font-scale));
    font-weight: 500;
    text-decoration: none;
}

/* Footer Refined */
.auth-footer {
    padding: 30px 20px;
    font-size: calc(13px * var(--font-scale));
    color: var(--text-secondary);
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
}

.footer-nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-top: 1px solid var(--input-border);
    padding-top: 20px;
}

.footer-left-links {
    display: flex;
    gap: 24px;
}

.footer-right-links {
    display: flex;
    gap: 24px;
}

.auth-footer a {
    color: var(--text-secondary);
    text-decoration: none;
}

.auth-footer a:hover {
    text-decoration: underline;
}

/* Mobile Adjustments */
@media (max-width: 768px) {
    .header-left .search-container {
        display: none;
    }
    
    .footer-nav {
        flex-direction: column;
        gap: 20px;
        align-items: flex-start;
    }
    
    .footer-left-links, .footer-right-links {
        flex-wrap: wrap;
        gap: 12px;
    }
}

@media (max-width: 480px) {
    .auth-card {
        padding: 24px;
        border: none;
        box-shadow: none;
        background: transparent;
    }
    
    .auth-container {
        padding-top: calc(60px + env(safe-area-inset-top));
        padding-bottom: env(safe-area-inset-bottom);
    }
}