:root {
    --color-primary: #0095f6;
    --color-primary-dark: #0867ba;
    --color-background: #000000;
    --color-surface: #121212;
    --color-border: #262626;
    --color-text-primary: #ffffff;
    --color-text-secondary: #a8a8a8;
    --color-success: #31a24c;
    --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

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

html {
    background-color: var(--color-background);
}

body {
    font-family: var(--font-sans);
    background-color: var(--color-background);
    color: var(--color-text-primary);
    display: flex;
    min-height: 100vh;
    align-items: center;
    justify-content: center;
}

.login-container {
    display: flex;
    width: 100%;
    height: 100vh;
    max-width: 100vw;
}

/* LEFT SECTION */
.login-left {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(45deg, #000000, #1a1a1a);
    border-right: 1px solid var(--color-border);
    position: relative;
    overflow: hidden;
}

.login-left::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-image: 
        radial-gradient(circle at 20% 50%, rgba(255, 100, 200, 0.1) 0%, transparent 50%),
        radial-gradient(circle at 80% 80%, rgba(0, 150, 255, 0.05) 0%, transparent 50%);
    pointer-events: none;
}

.left-content {
    position: relative;
    z-index: 1;
    text-align: center;
    max-width: 500px;
}

.instagram-logo {
    margin-bottom: 3rem;
}

.instagram-logo svg {
    width: 400px;
    margin: 0 auto;
}

.tagline {
    font-size: 2.5rem;
    font-weight: 300;
    line-height: 1.2;
    margin-bottom: 3rem;
    font-family: var(--font-sans);
    letter-spacing: -0.5px;
}

.tagline .highlight {
    background: linear-gradient(90deg, #f77737 0%, #ffa700 25%, #fcb045 50%, #ff1d25 75%, #d6249f 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    font-weight: 600;
}

.phone-mockup {
    position: relative;
    width: 340px;
    height: 600px;
    margin: 0 auto;
    background: var(--color-surface);
    border-radius: 60px;
    padding: 12px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.5);
    border: 8px solid var(--color-border);
}

.phone-mockup::before {
    content: '';
    position: absolute;
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 150px;
    height: 25px;
    background: var(--color-surface);
    border-radius: 0 0 30px 30px;
    z-index: 10;
}

.phone-content {
    width: 100%;
    height: 100%;
    border-radius: 50px;
    overflow: hidden;
}

.phone-content img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

/* RIGHT SECTION */
.login-right {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: var(--color-background);
    padding: 2rem;
}

.login-form-container {
    width: 100%;
    max-width: 400px;
}

.back-button {
    background: none;
    border: none;
    color: var(--color-text-primary);
    cursor: pointer;
    padding: 0.5rem;
    margin-bottom: 2rem;
    font-size: 1.5rem;
    transition: opacity 0.2s;
}

.back-button:hover {
    opacity: 0.7;
}

.login-title {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 2rem;
    color: var(--color-text-primary);
}

.login-logo {
    display: block;
    margin: 0 auto 2rem auto;
    width: auto;
    object-fit: contain;
}

.login-form {
    margin-bottom: 1.5rem;
}

.form-group {
    margin-bottom: 1rem;
}

.form-input {
    width: 100%;
    padding: 0.75rem;
    background-color: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: 0.375rem;
    color: var(--color-text-primary);
    font-size: 0.875rem;
    font-family: var(--font-sans);
    transition: all 0.2s;
}

.form-input::placeholder {
    color: var(--color-text-secondary);
}

.form-input:focus {
    outline: none;
    border-color: var(--color-primary);
    background-color: rgba(0, 0, 0, 0.5);
}

.form-input:invalid:not(:placeholder-shown) {
    border-color: #e0245e;
}

.login-button {
    width: 100%;
    padding: 0.75rem;
    background: linear-gradient(135deg, var(--color-primary) 0%, #00a3e1 100%);
    border: none;
    border-radius: 0.375rem;
    color: white;
    font-weight: 600;
    font-size: 0.875rem;
    cursor: pointer;
    transition: all 0.2s;
    font-family: var(--font-sans);
}

.login-button:hover {
    opacity: 0.9;
    transform: translateY(-1px);
}

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

.login-button:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.divider {
    display: flex;
    align-items: center;
    margin: 1.5rem 0;
    gap: 1rem;
}

.divider span {
    color: var(--color-text-secondary);
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.divider::before,
.divider::after {
    content: '';
    flex: 1;
    height: 1px;
    background-color: var(--color-border);
}

.facebook-login {
    width: 100%;
    padding: 0.75rem;
    background: none;
    border: 1px solid var(--color-border);
    border-radius: 0.375rem;
    color: var(--color-primary);
    font-weight: 600;
    font-size: 0.875rem;
    cursor: pointer;
    transition: all 0.2s;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    font-family: var(--font-sans);
    margin-bottom: 1rem;
}

.facebook-login:hover {
    border-color: var(--color-text-secondary);
}

.facebook-login svg {
    width: 18px;
    height: 18px;
}

.forgot-password {
    display: block;
    text-align: center;
    color: var(--color-text-secondary);
    text-decoration: none;
    font-size: 0.75rem;
    margin-bottom: 1.5rem;
    transition: color 0.2s;
}

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

.signup-section {
    text-align: center;
    margin-bottom: 1.5rem;
}

.signup-section p {
    font-size: 0.875rem;
    color: var(--color-text-secondary);
}

.signup-link {
    color: var(--color-primary);
    text-decoration: none;
    font-weight: 600;
    transition: color 0.2s;
}

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

.meta-branding {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    color: var(--color-text-secondary);
    font-size: 0.75rem;
    font-weight: 500;
}

.meta-branding svg {
    width: 16px;
    height: 16px;
}

/* RESPONSIVE DESIGN */
@media (max-width: 1024px) {
    .login-container {
        flex-direction: column;
    }

    .login-left {
        min-height: 300px;
        border-right: none;
        border-bottom: 1px solid var(--color-border);
    }

    .login-left::before {
        background-image: 
            radial-gradient(circle at 20% 50%, rgba(255, 100, 200, 0.05) 0%, transparent 50%),
            radial-gradient(circle at 80% 80%, rgba(0, 150, 255, 0.02) 0%, transparent 50%);
    }

    .tagline {
        font-size: 1.75rem;
        margin-bottom: 1.5rem;
    }

    .phone-mockup {
        width: 280px;
        height: 500px;
    }

    .login-right {
        padding: 2rem 1rem;
    }

    .login-form-container {
        max-width: 350px;
    }
}

@media (max-width: 640px) {
    .login-container {
        height: auto;
        min-height: 100vh;
    }

    .login-left {
        padding: 2rem 1rem;
    }

    .left-content {
        max-width: 100%;
    }

    .tagline {
        font-size: 1.5rem;
    }

    .phone-mockup {
        width: 240px;
        height: 420px;
    }

    .instagram-logo svg {
        width: 150px;
    }

    .login-title {
        font-size: 1.25rem;
    }

    .form-input,
    .login-button,
    .facebook-login {
        font-size: 16px; /* Prevents zoom on iOS */
    }
}

/* ANIMATIONS */
@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.login-form-container {
    animation: slideIn 0.6s cubic-bezier(0.22, 1, 0.36, 1) forwards;
}

/* FOCUS STATES */
.form-input:focus-visible,
.login-button:focus-visible,
.facebook-login:focus-visible,
.back-button:focus-visible {
    outline: 2px solid var(--color-primary);
    outline-offset: 2px;
}

/* LOADING STATE */
.login-button.loading {
    position: relative;
    color: transparent;
}

.login-button.loading::after {
    content: '';
    position: absolute;
    width: 16px;
    height: 16px;
    top: 50%;
    left: 50%;
    margin-left: -8px;
    margin-top: -8px;
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: white;
    animation: spin 1s linear infinite;
}

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

/* MESSAGE STYLES */
.message {
    padding: 1rem;
    border-radius: 0.375rem;
    margin-bottom: 1rem;
    font-size: 0.875rem;
    font-weight: 500;
    animation: slideIn 0.3s cubic-bezier(0.22, 1, 0.36, 1) forwards;
}

.error-message {
    background-color: rgba(224, 36, 94, 0.1);
    border: 1px solid #e0245e;
    color: #ff6b9d;
}

.success-message {
    background-color: rgba(49, 162, 76, 0.1);
    border: 1px solid #31a24c;
    color: #31a24c;
}

.warning-message {
    background-color: rgba(255, 193, 7, 0.1);
    border: 1px solid #ffc107;
    color: #ffc107;
}