:root {
    --primary-color: #6366f1;
    --primary-hover: #4f46e5;
    --bg-dark: #0f172a;
    --card-bg: rgba(30, 41, 59, 0.7);
    --text-main: #f8fafc;
    --text-muted: #94a3b8;
    --border-color: rgba(255, 255, 255, 0.1);
    --error-color: #ef4444;
}

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

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-dark);
    color: var(--text-main);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    overflow: hidden;
    position: relative;
}

/* Fondo animado */
.background-animation {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 0;
    overflow: hidden;
}

.blob {
    position: absolute;
    filter: blur(80px);
    border-radius: 50%;
    opacity: 0.5;
    animation: float 10s infinite alternate ease-in-out;
}

.blob-1 {
    width: 400px;
    height: 400px;
    background: #6366f1;
    top: -100px;
    left: -100px;
}

.blob-2 {
    width: 500px;
    height: 500px;
    background: #8b5cf6;
    bottom: -150px;
    right: -100px;
    animation-delay: -5s;
}

@keyframes float {
    0% { transform: translate(0, 0) scale(1); }
    100% { transform: translate(50px, 50px) scale(1.1); }
}

/* Tarjeta de Login */
.login-container {
    position: relative;
    z-index: 1;
    width: 100%;
    max-width: 420px;
    padding: 20px;
}

.login-card {
    background: var(--card-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--border-color);
    border-radius: 24px;
    padding: 40px;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
    animation: slideUp 0.6s cubic-bezier(0.16, 1, 0.3, 1);
}

@keyframes slideUp {
    0% { opacity: 0; transform: translateY(40px); }
    100% { opacity: 1; transform: translateY(0); }
}

.brand-header {
    text-align: center;
    margin-bottom: 32px;
}

.logo {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 64px;
    height: 64px;
    background: linear-gradient(135deg, var(--primary-color), #8b5cf6);
    border-radius: 16px;
    margin-bottom: 16px;
    color: white;
    box-shadow: 0 10px 20px rgba(99, 102, 241, 0.3);
}

.brand-header h2 {
    font-size: 24px;
    font-weight: 700;
    margin-bottom: 8px;
    letter-spacing: -0.5px;
}

.brand-header p {
    color: var(--text-muted);
    font-size: 14px;
}

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

.input-group label {
    display: block;
    font-size: 13px;
    font-weight: 500;
    margin-bottom: 8px;
    color: var(--text-muted);
}

.input-wrapper {
    position: relative;
}

.input-icon {
    position: absolute;
    left: 14px;
    top: 50%;
    transform: translateY(-50%);
    width: 18px;
    height: 18px;
    color: var(--text-muted);
    pointer-events: none;
    transition: color 0.3s;
}

.input-wrapper input {
    width: 100%;
    background: rgba(15, 23, 42, 0.5);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 14px 14px 14px 42px;
    color: var(--text-main);
    font-size: 15px;
    font-family: inherit;
    transition: all 0.3s;
}

.input-wrapper input:focus {
    outline: none;
    border-color: var(--primary-color);
    background: rgba(15, 23, 42, 0.8);
    box-shadow: 0 0 0 4px rgba(99, 102, 241, 0.15);
}

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

.error-message {
    color: var(--error-color);
    font-size: 13px;
    margin-bottom: 16px;
    min-height: 18px;
    text-align: center;
    opacity: 0;
    transform: translateY(-5px);
    transition: all 0.3s;
}

.error-message.show {
    opacity: 1;
    transform: translateY(0);
}

.btn-primary {
    width: 100%;
    background: var(--primary-color);
    color: white;
    border: none;
    border-radius: 12px;
    padding: 14px;
    font-size: 15px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
    display: flex;
    justify-content: center;
    align-items: center;
    position: relative;
    overflow: hidden;
}

.btn-primary:hover {
    background: var(--primary-hover);
    transform: translateY(-2px);
    box-shadow: 0 8px 16px rgba(99, 102, 241, 0.25);
}

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

.btn-primary.loading span {
    opacity: 0;
}

.spinner {
    display: none;
    position: absolute;
    width: 20px;
    height: 20px;
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: white;
    animation: spin 0.8s linear infinite;
}

.btn-primary.loading .spinner {
    display: block;
}

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

.footer-text {
    margin-top: 24px;
    text-align: center;
    font-size: 13px;
    color: var(--text-muted);
}

.footer-text a {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.2s;
}

.footer-text a:hover {
    color: #8b5cf6;
    text-decoration: underline;
}