:root {
    --color-primary: #3b82f6;
    --color-primary-hover: #2563eb;
    --color-success: #10b981;
    --color-danger: #ef4444;
    --color-warning: #f59e0b;
    
    /* Light Theme */
    --bg-primary: #ffffff;
    --bg-secondary: #f8fafc;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --text-muted: #94a3b8;
    --border-color: #e2e8f0;
    --shadow: 0 1px 3px 0 rgb(0 0 0 / 0.1), 0 1px 2px -1px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);
}

[data-theme="dark"] {
    --bg-primary: #0f172a;
    --bg-secondary: #1e293b;
    --text-primary: #f1f5f9;
    --text-secondary: #cbd5e1;
    --text-muted: #94a3b8;
    --border-color: #475569;
    --shadow: 0 1px 3px 0 rgb(0 0 0 / 0.3), 0 1px 2px -1px rgb(0 0 0 / 0.3);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.3), 0 4px 6px -4px rgb(0 0 0 / 0.3);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.3), 0 8px 10px -6px rgb(0 0 0 / 0.3);
}

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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, 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;
    transition: all 0.3s ease;
}

.login-structure {
    position: relative;
    z-index: 100;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0;
}

/* Animated Background */
.background-animation {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 1000 1000"><defs><pattern id="arcade-pattern" x="0" y="0" width="100" height="100" patternUnits="userSpaceOnUse"><circle cx="50" cy="50" r="30" fill="rgba(255,255,255,0.1)" opacity="0.3"><animate attributeName="r" values="25;35;25" dur="4s" repeatCount="indefinite"/></circle><rect x="20" y="20" width="60" height="60" fill="none" stroke="rgba(255,255,255,0.2)" stroke-width="2" opacity="0.5"><animateTransform attributeName="transform" type="rotate" values="0 50 50;360 50 50" dur="8s" repeatCount="indefinite"/></rect></pattern></defs><rect width="100%" height="100%" fill="url(%23arcade-pattern)"/></svg>') center/400px;
    animation: backgroundMove 20s linear infinite;
    z-index: 1;
}

@keyframes backgroundMove {
    0% { transform: translateX(-100px) translateY(-100px); }
    100% { transform: translateX(100px) translateY(100px); }
}

/* Floating Elements */
.floating-element {
    position: absolute;
    opacity: 0.1;
    animation: float 6s ease-in-out infinite;
    z-index: 2;
}

.floating-element:nth-child(1) {
    top: 10%;
    left: 10%;
    animation-delay: 0s;
}

.floating-element:nth-child(2) {
    top: 20%;
    right: 10%;
    animation-delay: 2s;
}

.floating-element:nth-child(3) {
    bottom: 20%;
    left: 15%;
    animation-delay: 4s;
}

.floating-element:nth-child(4) {
    bottom: 15%;
    right: 20%;
    animation-delay: 1s;
}

@keyframes float {
    0%, 100% { transform: translateY(0px) rotate(0deg); }
    50% { transform: translateY(-20px) rotate(180deg); }
}

/* Theme Toggle */
.theme-toggle {
    position: absolute;
    top: 2rem;
    right: 2rem;
    background: rgba(255, 255, 255, 0.2);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    width: 50px;
    height: 50px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.3s ease;
    color: white;
    font-size: 1.2rem;
    z-index: 1000;
}

.theme-toggle:hover {
    background: rgba(255, 255, 255, 0.3);
    transform: scale(1.1);
}

/* Login Container */
.login-container {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(20px);
    border-radius: 20px;
    padding: 3rem 2.5rem;
    width: 100%;
    max-width: 450px;
    box-shadow: var(--shadow-xl);
    border: 1px solid rgba(255, 255, 255, 0.2);
    position: relative;
    z-index: 100;
    animation: slideIn 0.6s ease-out;
}

[data-theme="dark"] .login-container {
    background: rgba(15, 23, 42, 0.95);
    border: 1px solid rgba(71, 85, 105, 0.3);
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateY(30px) scale(0.95);
    }
    to {
        opacity: 1;
        transform: translateY(0) scale(1);
    }
}

/* Logo Section */
.logo-section {
    text-align: center;
}

.logo {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.5rem;
    margin-bottom: 0.5rem;
    animation: logoGlow 2s ease-in-out infinite alternate;
}

@keyframes logoGlow {
    from { filter: drop-shadow(0 0 10px rgba(59, 130, 246, 0.3)); }
    to { filter: drop-shadow(0 0 20px rgba(59, 130, 246, 0.6)); }
}

.logo img {
    height: 12rem;
    width: auto;
    display: block;
}

.welcome-text {
    color: var(--text-secondary);
    font-size: 1.1rem;
    margin-bottom: 0.5rem;
}

/* Form Styles */
.login-form {
    space-y: 1.5rem;
}

.form-group {
    margin-bottom: 1.5rem;
    position: relative;
}

.form-label {
    display: block;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
    font-size: 0.9rem;
}

.form-input {
    width: 100%;
    padding: 1rem 1rem 1rem 3rem;
    border: 2px solid var(--border-color);
    border-radius: 12px;
    font-size: 1rem;
    transition: all 0.3s ease;
    background: var(--bg-primary);
    color: var(--text-primary);
    outline: none;
}

.form-input:focus {
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
    transform: translateY(-2px);
}

.form-input:valid {
    border-color: var(--color-success);
}

.input-icon {
    position: absolute;
    left: 1rem;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-muted);
    font-size: 1.1rem;
    transition: all 0.3s ease;
    margin-top: 1.25rem;
}

.form-input:focus + .input-icon {
    color: var(--color-primary);
}

/* Password Toggle */
.password-toggle {
    position: absolute;
    right: 1rem;
    top: 50%;
    transform: translateY(-50%);
    background: none;
    border: none;
    color: var(--text-muted);
    cursor: pointer;
    font-size: 1.1rem;
    padding: 0.5rem;
    transition: all 0.3s ease;
    margin-top: 1.25rem;
}

.password-toggle:hover {
    color: var(--color-primary);
}

/* Remember Me & Forgot Password */
.form-options {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
    flex-wrap: wrap;
    gap: 1rem;
}

.remember-me {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.remember-me input[type="checkbox"] {
    width: 18px;
    height: 18px;
    accent-color: var(--color-primary);
}

.remember-me label {
    color: var(--text-secondary);
    font-size: 0.9rem;
    cursor: pointer;
}

.forgot-password {
    color: var(--color-primary);
    text-decoration: none;
    font-size: 0.9rem;
    font-weight: 500;
    transition: all 0.3s ease;
}

.forgot-password:hover {
    color: var(--color-primary-hover);
    text-decoration: underline;
}

/* Login Button */
.login-btn {
    width: 100%;
    padding: 1rem;
    background: linear-gradient(135deg, var(--color-primary), var(--color-primary-hover));
    color: white;
    border: none;
    border-radius: 12px;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.login-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 25px rgba(59, 130, 246, 0.3);
}

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

.login-btn::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 ease;
}

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

/* Loading State */
.login-btn.loading {
    pointer-events: none;
    opacity: 0.8;
}

.login-btn.loading::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 20px;
    height: 20px;
    margin: -10px 0 0 -10px;
    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); }
}

/* Error Message */
.error-message {
    background: rgba(239, 68, 68, 0.1);
    border: 1px solid var(--color-danger);
    color: var(--color-danger);
    padding: 0.75rem 1rem;
    border-radius: 8px;
    margin-bottom: 1.5rem;
    font-size: 0.9rem;
    display: none;
    animation: shake 0.5s ease-in-out;
}

@keyframes shake {
    0%, 100% { transform: translateX(0); }
    25% { transform: translateX(-5px); }
    75% { transform: translateX(5px); }
}

/* Success Message */
.success-message {
    background: rgba(16, 185, 129, 0.1);
    border: 1px solid var(--color-success);
    color: var(--color-success);
    padding: 0.75rem 1rem;
    border-radius: 8px;
    margin-bottom: 1.5rem;
    font-size: 0.9rem;
    display: none;
}

/* Footer */
.login-footer {
    text-align: center;
    margin-top: 2rem;
    padding-top: 2rem;
    border-top: 1px solid var(--border-color);
}

.footer-text {
    color: var(--text-muted);
    font-size: 0.85rem;
    line-height: 1.5;
}

/* Responsive Design */
@media (max-width: 640px) {
    .login-structure {
        width: 100%;
        gap: 0;
        padding: 0 1rem;
    }

    .login-container {
        margin: 1rem;
        padding: 2rem 1.5rem;
    }

    .theme-toggle {
        top: 1rem;
        right: 1rem;
        width: 45px;
        height: 45px;
    }

    .logo img {
        height: 8rem;
    }

    .form-options {
        flex-direction: column;
        align-items: flex-start;
        gap: 0.75rem;
    }
}

/* Dark theme specific adjustments */
[data-theme="dark"] body {
    background: linear-gradient(135deg, #0f172a 0%, #1e293b 100%);
}

[data-theme="dark"] .floating-element {
    opacity: 0.05;
}